I was 3 days late for my . An then when it started it was heavy during the day then very light or nothing at all at night and only lasted 5 days, on the sixth day I didn't have any bleeding at all, the next morning my boyfriend and I had normal, nothing different protected sex like we usually do and also that morning I started a very light bleeding, and it was more a light pink too, it lasted all day "TODAY" could I be pregnant?

Read the stickies, go buy a home pregnancy test if you think you may be pregnant.
I am a guy and I had gf's who periods would do this, and they weren't pregnant!
I just replying because nobody has, and my ex had some of these problems with her period at times.

Dynocompe is right. Buy a HPT if you are concerned. However, since you did have a period the chances of you being pregnant are slim and the reason you bled after sex is because there was still some left over blood in the vaginal vault. You will now have to wait until next month to see if your period comes.

I do hope you used protection.