I just don't know... and it's frustrating.

Samantha
Hi ladies!! I'm 30. Never pregnant and am currently TTC. My period has never been regular and am currently 4 days later than predicted. This tends to happen very often. 
I always get my hopes up and take 2-3 pregnancy tests and they if course all come  back negative. 
Should I feel different if I get pregnant?! What types of sumptoms should I be feeling?! I'm just tired of getting my hopes up and then being let down. 
Most of all I feel stupid asking these questions... shouldn't I know?? 
Ugh... I hate all of this.