Experiences in Meditation: Am I stucked?

As a starting reference, we can all consult MN10 as taught by the Buddha:

MN10:2.1: “Mendicants, the four kinds of mindfulness meditation are the path to convergence. They are in order to purify sentient beings, to get past sorrow and crying, to make an end of pain and sadness, to end the cycle of suffering, and to realize extinguishment.

There are four kinds of mindfulness meditation:

MN10:3.1: What four?
MN10:3.2: It’s when a mendicant meditates by observing an aspect of the body—keen, aware, and mindful, rid of desire and aversion for the world.
MN10:3.3: They meditate observing an aspect of feelings—keen, aware, and mindful, rid of desire and aversion for the world.
MN10:3.4: They meditate observing an aspect of the mind—keen, aware, and mindful, rid of desire and aversion for the world.
MN10:3.5: They meditate observing an aspect of principles—keen, aware, and mindful, rid of desire and aversion for the world.

Finding feeling unsatisfactory (i.e., "feeling stucked"), perhaps it might be worth studying mind and principles. MN10 is a good source for study and discussion.

You need to stop doing samatha meditation and do cultivation instead. Samatha meditation is difficult. Unless you are working closely with an excellent teacher, you won't be ready for samatha until stream entry.

Cultivation is bringing up wholesome qualities. Examples are: loving-kindness, compassion, empathetic joy, equanimity, and the nine virtues of the Buddha.

Practicing now daily. Around 1 hour. My concentration is far better. I realize bodily experiences – mainly feeling "light", sometimes "happy".

With developing momentum in the practice, concentration is readily available. With the lightness, the first thing you're noticing here is the perception of the body begins to change. It moves from a state of solidity to one of fluidity. In my personal understanding, this could be the beginning of breaking into the first arupa ayatana where the perception of space is undermined by its potential non-perception of space, resulting in lightness of the body and eventually free-floating in boundless space, which is the opposite of your 'limited' understanding of space. The happiness is a symptom of letting go of these solid-like perceptions, which are elaborate illusions. It's not actually fully arupa, you're just knocking on the door, so to speak. When you get to the last arupa ayatana - neither perception or non-perception - and penetrate that, all ideas about space, whether limited, boundless or otherwise disappears. It took me 18 months to work through that particular phase. I then found myself at the doorstep of the 8th fetter.

The other possibility is that first jhana may be opening up for you, so bare that in mind, too. In any case, one does not need to have worked through an experiential understanding of the 4 jhanas in order to get to the arupas (formless spheres). The arupa ayatanas are all about our perception, the way we see ourselves and the world, the way the mind brings into form whatever the senses are exposed to (perceptions).

The 4 jhanas are largely about developing a familiarity with hightened rapture and pleasure - which sometimes might seem other-worldly and fascinating - such that one breaks into equanimity, the last two jhana states. My first and second jhana exploration sometimes caused my muscles to tremor, the rapture was so intense!

How do I not get distracted from the ultimate goal?

Distraction is part of the exploration. In fact, it is the disturbances that are produced by these distractions that motivate us to find answers to the human condition. Distractions won't go away, but the way in which you think about them will. In essence, all mental resistance resistance will stop.

anxious, that ... I do not make further progress... ultimate goal.

This idea of progress to the ultimate goal is a fetter. Your meditation has to be free from petty concerns like this.

Recognize this for what it is: the monkey of samsaric mind looking for a next branch to grab onto. Your meditation has to stop grasping at ideas of future existence, whether positive/desirable or frightening/undesirable.

Do not worry about the bliss that comes from meditation, in fact that's the kind of bliss that works like the soap to wash the mind, that's what the Buddha said. Enjoy it and use it.

At some point the bliss will start wearing off, so at that point do not cling to it. That's it, do not attach to the bliss when it ends. No need to worry about it when it's here. Do not cling to it nor chase it nor go against it.

The idea of Buddhist meditation is to arrive at this very open, boundlessly open mind, with no conceptual ground and no boundary conditions.

In this mind, vast and open like the open ocean, there's no ultimate goal and no attachment to any condition, including bliss. It is attained by letting go. It is much much bigger than smallish things like the ultimate goal, experiences of bliss and suffering, concepts of birth and death.