Could I be pregnant?

Jyoti
Hey everyone so last month my period was on April.16 I was due for my period this month on May.14, it never came. I took 2 of those cheap pregnancy test and it came up negative. Today I'm 11 days late and still no period. I have never been more than 9 days late before. I've been feeling like I'm going to get my period for about a week but everytime I go to the bathroom, there's nothing. Could I be pregnant? And if so why isn't the test showing positive or where the hell is my period if I'm not! 
Also I plan to take a FRER test this Friday but if it comes negative I plan to wait till june 1 atleast and then go to the doctor. Should I be worried as to why it doesn't show positive if I am, and if I'm not where's my period?