Need help/tmi

So here's the deal. I started my period around Wednesday the 14th and had light flow for about a week. I missed a few birth control pills around here but then got right back on track. For another week after I ended my period I experience brown and red discharge with light cramping. Now for the past three days I've been bleeding with small clots. I'm just a little worried and I don't know what's going on. This is very unusual for me. Please help. Thanks!