Could I be pregnant after my period?

7 weeks ago I had unprotected sex, only birth control was withdrawal method. I had my period as usual 3 weeks after, then as my second cycle comes around, my body has started changing. Boobs growing, sore and dark nipples, non-stop peeing, high School football player hunger, and now...a missed period.

I should've started 3 days ago, but today I have light-pink discharge and slight cramping. I'm supposed to wait 2-4 days before taking a pregnancy test.

Could I possibly be pregnant even after I had a period?