Hook effect?

I’m 5 weeks 5 days and I’ve been testing about every 2 days since 3 weeks 5 days for reassurance until my ultrasound next week. The control line on my test faded this past weekend, and now it’s coming back and I was scared that my hcg must be dropping, until I read about the hook effect.

Supposedly the hook effect is when your hcg becomes really high after 5 or 6 weeks or more, the hcg tests cannot correctly read the high levels, and your test line becomes lighter the higher your hcg rises. I know my hcg started out kinda high because I had 2 blood tests early on. Could this be the hook effect? Has anyone else experienced this?