Weird Period

Usually my periods are anywhere from 3-5 days long. This last one was a day and a half. I am not sure whats up with that? I had a pretty regular flow for 1 day and them spotty the next day and that lasted until late afternoon. Anyone know what could have caused this? My boyfriend and I are apart right now because of work but we had spent the week before together and well....I suppose pregnancy is always an option. I havent been stressed more than usual and havent had any other drastic changes that could have thrown it off. I had my yearly pap about 2 days before it started. Just wondering what could be going on. Have not heard the results of the pap yet.