First response pink indents losing my mind

I've take 6 or 7 first response tests all with a second pink line but they are not getting darker. Clear blues all negative. Digtal negative..... I feel like I'm losing my mind with these first response tests. I lost twins back in November. And I thought maybe first response was picking up left over hcg but my blood test is at 1 on the 12th. My ultrasound shows there is nothing left. And their urine test came back negative. However when I came home I took another first response that still came back with that darn faint second pink line..... I am going absolutely bat crap crazy. I just want to understand what's happening with my body. I keep saying I'm not pregnant and the tests are just that broken. But I'm only at maybe 10 or 11 dpo. With my last pregnancy I had early postives and early digital test. Anyone else experience this?