Nexplanon

So I got my implant in December last year and haven't had sex until Wednesday, the 19th, and we had unprotected sex and he said he finished inside of me but only a little bit. Should I worry about anything? Earlier I felt some stomach cramps and my vagina smelled like period blood but no period. Also, should I be worry about my implant not being where my insertion scar is?? It's a little below it (above the red box) and slanted and now I'm just paranoid and scared 😂😅