So confused!

Can someone explain to me why my pregnancy tests are JUST now getting stronger lines? I’ve already had a few ultrasounds due to being so confused with taking pregnancy tests and them being all over the place. I had a miscarriage 3 months ago. I had my ultrasound yesterday and just took a test just because I want my lines to get darker and it’s actually dark today! But I never got a BFP. I haven’t been able to go on base due to my urine not having enough HCG for their urine tests so they wouldn’t bother doing a blood test for me. So I’ve been going off base here in a foreign country just getting ultrasounds done. It’s been so hectic and exhausting 😭