So confused

My period is 18 days late...ive taken 6 pregnancy test over the past 18 days and spread them out. So they weren't all on day 5 of my missed period but I took one skipped a few days, took one skipped a few days so on and so forth. Anyways I don't think I'm preggo but I'm not having any cramps or anything like my period is about to start. Also my eating habits haven't changed and I'm not morning sick and also not more sleepy than usual. Any ideas?? Anything would help. I scheduled a doctors apt but they're booked until middle of next month! But anything?