Spotting during fertile week

I had sex a day after my period is over, and the day after. Cant remember the next time i had sex again, but the last time I had sex was two days ago.
All of the sudden my left boob hurt, i have cramps, and im spotting. Yesterday i had this pink gooey thing on my underwear. Im on my fertile week, im wondering whether im pregnant or is it normal to have brown spots during my fertile week. Please help?