[1245Berlioz]

I got my period on February 14th, and it lasted until about the 21st. Two days later, so on the 23rd I had sex with my boyfriend and the condom came off and he finished inside me. The next day I took plan b one step. I didn't have any symptoms until about four days later. I had bad mood swings, bleeding, cramping, headaches, and was very very tired. This lasted for about four days or so, aka until about the 28th or 29th of February. I didn't get my period all of March, I did take a pregnancy test on the 15th of March and it was negative. So, my question is could I be pregnant? I know false negatives can happen, and sometimes pregnancy tests don't work if taken too early. If you could give me any information you have, that would be great! Thank you!