Miscarriage?

So I've noticed how I've been having a lot of pain in my stomach and cramps that hurt more than normal. I've also experienced bleeding for about 8-9 days when usually my period is only 5 days and it's heavy and it's bright red. I just recently about a month ago got my birth control shot for the first time. Could my symptoms be from a miscarriage or is it just my body adjusting to my birth control. I thought I could be pregnant before I started my period and me and my boyfriend were suppose to take a test when I got back from out of state but my period had started so we didn't bother , but my family is known for a lot of miscarriages and I'm kind of scared. I would love to hear your guy's opinion it would be deeply appreciated.