Short breath during meditation

[Shadow]

I've been meditating for 10 months. I am observing my nostrils- breathe in and out. When I meditate, after the 5th minute my breath becomes really short and I feel like my chest area has become very heavy and I continue observing that, but the body does not take deeper breaths. My last meditation was even more strange- the breathing in continued for about 2 and a half seconds, holding in for 1 sec., breathing out for 2 and a half seconds and not breathing for another second. The intake of breath is really small- I barely feel the air in the nostrils- and I know this is a normal thing in meditation, but are such short breaths normal?

[Timothy]

May I ask, after these ten months...what can you tell of/about your motive to practice and expectations thru meditation.

[Shadow]

I'll have to explain more thoroughly. The short breath and the heavy chest feeling I get in meditation are uncomfortable. This breaks my concentration and my mind starts to wander, count seconds etc. And I have heard that people feel bliss in meditation. My question is whether that is normal to occur in meditation? And if not, what am I doing wrong?
My motive to practice is to explore the Self. I'm trying to hold back my expectations because they can be obstacles.

[CFTraveler]

It's normal. Automatic breathing is shallow, and after a while, your body goes on automatic, even if you're consciously watching it.