Still pregnant?

So I got these positive tests. Bottom is from Tuesday afternoon, middle from Wednesday afternoon and top is Thursday morning. Wednesday evening I had sex and started bleeding afterward. Not too much, just made me think maybe I was crazy and they weren't positive after all. Well Thursday morning (after I take the top test) I start spotting a little and cramping pretty bad. Then I start bleeding. And I'm talking about heavy flow blood dripping out of me as I sit on the toilet bleeding. I called my doctor and they had me come in for blood work to confirm the pregnancy and get quantitative blood levels. I haven't gotten the results back yet. So I'm sitting here super sad because I think I'm having an early miscarriage. Then I start wondering if maybe the line on a test would be darker by now. I know that's not a good way to measure levels or anything but I have no information right now and I'm just sad. So I went out and bought another box of tests and took one.

This is the one I just took. It looks darker than the others. Has anyone had this happen? All the bleeding and cramping and still been pregnant? I didn't expect the line to be darker. I don't know what to think. I'm so scared to actually let myself think I could be pregnant in case I lose it.