How early can we find out?

Hey ladies. I had my normal period the last week of January as normal (so just 2 weeks ago) than I had sex on February 2nd (last Saturday) and he did not pull out in time. I took a plan B the next day. This past Thursday I started to bleed HEAVILY out of the blue. My periods are always so scheduled and normal, so this random bleeding is so shocking. My question is if I went to the doctor to get blood drawn to be tested for pregnancy would it even be accurate after only 2 weeks? Or is it too early to know?