can i still be pregnant or is something else going on???

I had unprotected sex back in november(havent had sex since) around the time my period was due, 2weeks later i started cramping and hurting in my lower abdomin and 2 weeks after that i started bleeding. up until now i didnt think anymore about it but in the last few weeks i have started to feel like movement and a tightening feeling in my abdomin and i have put on a little weight, with me being a little over weight i really dont see a big change in the way i look. could i still be pregnant??? Please i need help dont know what to think.