Why am I nauseous, cramping and bleeding after my period ended

Toya

So I started my period 2 days early on oct.13 and it ended on oct.15 it’s usually 5 days long but it was only 3 days long and wasn’t a very heavy period it was a little lighter than usually so one oct.16 I was nauseous most or the day and on oct.17 I was still nauseous and later that night I could really eat and started to throw up as well and this morning oct.18 I’ve started cramping and bleeding a little not heavy but light I have no clue what is going on this has never happened to me before yes I am sexually active my boyfriend and I don’t use condoms he pulls out