Hcg levels after ectopic

I unfortunately had an ectopic at 9 weeks and bad my right tube removed Wednesday. I have had very high hcg levels from the start of my pregnancy, I'm just wondering how long until hey drop? I've been bleeding with the most pain cramps of my life for the past day, so I was curious if my levels went down yet so I took a hpt, and was surprised to see I'm still getting tests where the test line is darker than the control :( wondering if anyone has any similar situations?