missed period, negative test.

I had a miscarriage in March due to a blighted ovum. I have had normal periods like clock work since this happened. It is now September 11th, and I haven't seen a period since July 31st. Since i have been pregnant before i do know what it feel like. I don't have sore breast, and my aerola ins't darker. However i do sleep much more, my lower back hurts like cramps, and when i don't eat i get very nauseous and have an upset stomach and i pee more. I feel pregnant but i have had four negative test, not all back to back either was recently today. i haven't taken any with first morning urine so i will try that. if someone could write me and let me know if they have had a similar situation and ended up pregnant id appreciate it. Thank you for reading, and I will keep everyone posted.