Ok, me and my fiancé, who already have a child together have been having sex a lot.

Ive been on the depro shot, but I recently stopped getting it back in April.
I've been on my period for two weeks now and still going. We have had sex a couple times every day since I've been on it... unprotected by the way. I was just wondering if it was possible for me to get pregnant since I am on my 'cycle' ? I need to know!

Yes

How likely is it though? Do I have a good chance of getting pregnant or is it a low chance?

Since we don't know if you are ovulating, we can't tell you if the chance is high or low. If you are not ready to have another baby, you SHOULD be using protection every time you have sex.

Yes, it happens all the time, if you don't want to become pregnant then you don't have unprotected sex ( and even when on birth control it is not 100 percent effective