I'm not trying to conceive anymore but I had strange spotting which I've never had before .. and my period should be…

I'm not trying to conceive anymore but I had strange spotting which I've never had before .. and my period should be here Wednesday but today I had a bit of cramping so I took a pain killer and later felt myself bleed so I went to the bathroom and wiped I saw blood and figured I must be starting early and put a tampon in and about 2 hours later when I went to the bathroom it was nothing or the tampon or when I wiped so I put a panty liner on and when I got home still nothing ...could it be implantation bleeding ?