I got off the depo shot in may I started back getn my periods they wpuld last for 4 days now I haven't had a period in three weeks until my boyfriend and I had unprotected sex a week ago prior to that like three or two days later my period came on I usually last for four days but today is the fifth day... im wondering if I could be pregnant

Typically, having a period means that you aren't pregnant. However, you have had unprotected sex, so pregnancy is a possibility. You will have to wait to see if your next period comes as expected. If not, wait until it is two weeks late then test using first morning urine.