How Soon Can Pregnancy Be Confirmed After An Intercourse?

Quick Question: My boyfriend and myself had unprotected sex on day 26 of my cycle. I'm not on birth control and he ejaculated inside of me. On day 28, I had my scheduled period (However, it only lasted 3 days instead of its normal 5). Now, about 14 days post period I'm having some spotting (This has been going on for about a week). I'm worried I'm pregnant. Is it soon to take a pregnancy test? Any insight?