What Is This??

I got my period a day earlier and that was friday 14th it ended wednesday 19th and then I started cramping again yesterday and today just now am spotting and the blood is like a rust red color. This has never happened to me before so I dont really know what is going on. Could anyone ease my mind and tell me what this is or could be from? Thanks In Advance. Also my husband and I had sex my last ovulation date but I honestly doubt I'm pregnant just due to me have my period. So thats out of the question.