Early period...? Pregnant? ?

This past friday my period came on, yet it wasnt supposed to come on till the 21st. I usually have symptoms prior to getting it but this time i didn't. The first 2 days it was really heavy with blood cloths, and no severe pains, only minor cramps for a couple hours. 3rd day i was barely bleeding and today (4th day) its just minor spotting. My periods have always been 7 days long , and i have always bleed the whole 7 days. My boyfriend and i are very active and we never use protection. Around a month ago he came inside of me a little bit. Could i be pregnant? Or should i be worried about a miscarriage???