i started my rigorous ab training today and my abs were like rock hard but after i was done my stomach looked like it was full..is this normal?

Hmm, I got the same too. I need to improve my Diet, I think. Maybe you need to too.

If you have a decently high amount of bodyfat then building your abs will make your stomach bigger, but it will all pay off once you get the fat out of there.

If you can feel the abs and they are solid but it feels squishy on top, that is a nice layer of body fat.

That is why most people might have a 6 pack and aren't showing it.

Tighten up the diet and that should take care of that issue.

one word....CARDIO! goodluck.

Dude...the word is Diet+Resistance Training!

Cardio increases caloric expenditure a bit, but only if calories are not very low!
 
In fact, research showed that cardio alone is very ineffective for weight loss...average is only 1.6% weight loss.  However, with Very intense and extensive cardio, subjects were able to lose 12-25 pounds.

A change in diet is more effective over time.

The two together are quite powerful.  But D+T is more effective than the C word.

If you do lifting and cardio and are not eating right to support muscle, you lose about 25% or more of your weight from muscle!

If you are lifting and have an appropriate diet (not too low calories) you can lose body fat and maintain or even increase muscle.
 
In fact research comparing Diet only / Resistance only / Diet+Resistance  - <dropping 1000 calories>  showed:
There was a loss of 20% more fat from the Diet+Resistance training combo - while still gaining some muscle.
The resistance only gained muscle and lost a small amount of fat.
 
Dropping calories too low caused the body to resist losing weight so that no effect from training is observed.  Though strength still increases!  Due to neural improvements!
 
Cardio is an effective way to increase overall calorie expenditure at a set amount, but it is not THE most effective way.