Hi. I had unprotected sex on 22&23rd Mar I panicked and took morning after pill 26Mar at 6pm way over 72hrs. Then I had unprotected again on 29, 30 mar I was due my period on 30th Mar, took pregnancy test 29th negative. Unprotected sex again 2 and 4 Apr. I took a pregnancy test on 2nd Apr was negative. . On 5th Apr I had very light brown discharge when I wiped. This carried onto Sat morn so I presumed it was my period and started taking the pill. I didn't have any bleeding or spotting after the Sat. Took another test 12th Apr negative again. I read on net the brown discharge was because I had conceived so I stopped the pill on the 17th. Could I be pregnant?
I have been peeing a lot, been really exhausted, sore nipples and cloating, nausea for the first week.

It could still be too soon. I would wait another week, and if your period still was not here, I would go get a 2 pack test, and then go from there. But it sounds to me like you could very well be pregnant. Good luck!

I'm confused. You got the morning after pill, but continue to have unprotected sex? I'm fearful for you because you have a LOT to learn.

First, brown discharge is not necessarily a sign of pregnancy. In fact, its considered "old blood".
Second, the morning after pill can cause bleeding, possibly even the brown you experienced.
Third, if you are pregnant, those tests would have been taken too early to give a correct response. Wait until you're late for your period before you test again.
Fourth, get on Prenatal vitamins ASAP. If you are pregnant, your baby needs them. If you're not pregnant, start taking them anyway. If you're having unprotected sex, your body needs to be ready to sustain a pregnancy that could happen at any time. Prenantals can help prevent Neural Tube Defects (http://www.nichd.nih.gov/health/topics/neural_tube_defects.cfm)among other things. They work best if they've been in your body for a while before conception.