What exactly IS implantation bleeding

Hello I’m expecting my period tomorrow or today. I had unprotected sex a little over a week ago (bad idea I know) no ejaculation was involved. The sex lasted less than 30 seconds before I told him it was a bad idea and I couldn’t continue. I never took proper high school sex Ed because my school ONLY taught about abstinence so I know absolutely NOTHING about sex.

I wanted to know what implantation bleeding looks like so I don’t confuse my period with implantation bleeding. And when implantation bleeding happens.

Can you confuse the two or are they drastically different?

Thanks xx