Hi guys  i am so confused right now and am wondering if any one can help.

do I slept with one guy a lot up until the 11th  April but foolishly had a one night stand at 1 am one the 14th 

I took a clear blue test on Wednesday 3rd may  by chance before bed and got a shock "pregnant 2-3 " I left it alone and because I didn't believe it done another on Friday 4th and shock again it said "pregnant 3+ "  The thing is my cycle is 35-40 days and my lmp was 27th march so I am thinking I must have a long lutheal phase or something is not right because I'm figuring concept would have to have been the 12th or 13th but then reading how clear blue is usually behind with people's dates I'm thinking even earlier maybe around the 8th - 10th. But by my cycle predictions it would have to have been around the 18 which would have put me less than 3+ on the Friday. 

I'm going crazy !