Could i have gotten pregnant?

I am on a daily birth control pill. I always take it soon after I wake up, though that's not always the same time every day. My boyfriend and I always use a condom, however this month we had intercourse for about a minute before putting it on. Could I have gotten pregnant from that? I'm feeling like I need to throw up and I am very tired and getting frequent headaches. My period is not due for another 5 days, so it is too early to take a home test. I took one anyways and it came out as negative, but I tested too early for it to be accurate. I would really like opinions in these next five days as to what somebody else thinks?