I have an irregular period can I still get pregnant/ Also how would I know if I am if my period do not come on every month

Yes, you can still get pregnant with an irregular period. Whether it is regular or not, you are still fertile.

The only way to be sure if you are pregnant is to take an HPT. Take one about once or twice a week around the time you are supposed to start your period. Do this for about a month. If you never show a positive sign, then your period is on its way eventually.

With irregular periods, and not knowing exactly when to test for pregnancy, I would recommend getting on some sort of birth control. :)