How can i tell the diff. if i am preg. or if im about to start?

yes i know this sounds stupid.. i am 26 years old and i cant tell the diff. i have been taking fertility meds and i am hoping it works.. well i know i should be starting my period around the 11th.. i know the common things that happen before a period. Like breast hurting and things like that.. but a little over a week ago i started waking up in the middle of the night sick to my stomach. i would stay sick for about an hour then i would finally fall back asleep. And i am also using the bathroom a little more then normal. But i took a test at the time and it was neg. I have a doctors app but it isnt till August.. so are there any other little things i can look for like a certain way of being sick. is it a normal kinda of sickness in your stomach? Yes i am going to take another test but i am waiting till its closer to the time im suppose to start.