no period and negative pregnancy test!

My husband and I have been trying to convince for over 5yrs. I was on the iud for the first two years of our relationship and then we decided we wanted to try to have a child. I already have a child from a previous relationship who is 9 but after years of trying and heartbreak we decided to stop and focus on us. Well this month my period was supposed to start and I only spotted once this month and it was very light. I have taken 2 pregnancy tests that came up negative! but still no period! I have tender breasts and cramping like I'm going to start my period but nothing. I'm nervous to take another test idk if I should just wait another two weeks when my period is supposed to come again or test again? I hate not knowing but I don't think I can handle the heartbreak of a negative test.