I just cant stop crying today

I never had a problem (I do have 3 kids) until I had a miscarriage in September at 3 months. It shook my world. We waited a cycle and then started trying to conceive. the first cycle we tried I had a positive test and then miscarried a week after af was due. This is the 3rd time now I’ve had positive tests. And I’m two days late today and my temp dropped. It’s just making me crazy. I feel like something is wrong with me. This whole week I’ve been afraid to be happy about the positive and I was right I just have these faint tests that don’t get darker. Af hasn’t come yet but it probably will. I’m so exhausted of holding onto hope. I just needed to vent. I’m just really sad. My test got darker yesterday and I was really excited and I just took a test today and there’s nothing. I feel like I’m broken