Anapanasati Buddhist meditation

I apologize for making an answer that should be a comment but I don't have enough rep to comment. My teacher always says that, in general, you should feel good after practicing meditation. His rule of thumb is that if you feel good, clear-minded, and refreshed, you are probably doing it right. If you feel dull, sluggish, or worse than when you started, you are probably doing it wrong and may be causing insidious harm. It sounds to me like you need to work on following the three golden rules. Best of luck!

All these experiences you get are due to fabrications.

You should actively calm the fabrication. To do that:

• If you have a pleasant / unpleasant sensation somewhere bring it to your attention for a while - initially just bringing it to your attention will not make it go away but later stages it will just pass away
• When you mind wanders a way just before brining it to the subject asses the sensations around your head and body
• When focused on the breath focus on all aspects of the breathing. Duration and start to stop
• Focus on particular bodily sensation (expansion / contraction and oxygenating) with no imagination or verbalisation of sensations related to the breathing
• Focus on the mind wondering and thinking and try to focus on the breath exclusively to reduce verbal fabrication
• Focus on sensations resulting from metal states or content and sensations resulting from perception and outlook of the world you have. Note biggest source of misery is the perception of oneself.
• Initially you will have gross solidified sensation in your body. By bringing them to your attention they will pass away. Then you will have pleasant sensations. By being attentive to them without missing any part of the body they also will pass away leaving neutral sensation.

Also note meditating 15 minutes may be inadequate. At least do 1 hour in the morning and 1 hour in the evening / night. If possible more.

This little plant of Dhamma requires service now. Protect it from the criticism of others by making a distinction between the theory, to which some might object, and the practice, which is acceptable to all. Don’t allow such criticism to stop your practice. Meditate one hour in the morning and one hour in the evening. This regular, daily practice is essential. At first it may seem a heavy burden to devote two hours a day to meditation, but you will soon find that much time will be saved that was wasted in the past. Firstly, you will need less time for sleep. Secondly, you will be able to complete your work more quickly, because your capacity for work will increase. When a problem arises you will remain balanced, and will be able immediately to find the correct solution. As you become established in the technique, you will find that having meditated in the morning, you are full of energy throughout the day, without any agitation.

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When you go to bed at night, for five minutes be aware of sensations anywhere in the body before you fall asleep. Next morning, as soon as you wake up, again observe sensations within for five minutes. These few minutes of meditation immediately before falling asleep and after waking up will prove very helpful.

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Daily meditation of two hours and yearly retreats of ten days are only the minimum necessary to maintain the practice. If you have more free time, you should use it for meditation. You may do short courses of a week, or a few days, even one day. In such short courses, devote the first one third of your time to the practice of Anapana, and the rest to Vipassana.

Source: The Discourse Summaries by S.N.Goenka

Just breath naturally. Controlling the breath is a different practice all together called Pranayama, and that is generally a Hindu practice. In Anapanasati, the breath shouldn't be controlled or forced but will slowly calm down all on its own. Eventually breathing becomes very slow and shallow, but in order to get there you have to learn to let go and let the breath 'do its own thing' and just watch.

Also, make sure that you are keeping your attention on the breathing rather than the counting. I personally recommend only using counting at the beginning of a meditation session and when the mind becomes distracted, but not the whole time.

Cripes! Don't do that! Anapanasati isn't controlled breathing as in yoga or some forms of Taoist meditation. All you are supposed to be doing is watching the breath. Notice short breaths as short breaths, long breaths as long breaths. Experience breathing in and out. But by no means should you try to control your breath. Mindfulness is the exact opposite of control! Let breathing just be breathing.