Pregnant?

Hi, so the last day of my period was the 8th of this month and I had unprotected sex on the 10th, 13th, 17th and 21st, however we used the pull out method and I'm pretty sure I didn't feel any semen in/on me. Problem is I'm having light red spotting when I wipe, it's not a lot just one wipe and it disappears but when I peep gain the same thing happen, I am not having any cramps or anything of that sort and I just noticed this today. Is it possible that I may be pregnant, I am freaking out!!