Ovulating or Not?

I had a miscarriage Nov. 14th at 9weeks. Had a follow up with my OBGYN on Nov. 30th. She said we could start trying right away. Hormone level was where it should be. I started using Clearblue advantage ovulation sticks Nov. 26th and have gotten 2 days of lows and 7 days of highs. I have not had a period since but it’s only been 3 weeks since the miscarriage. Why am I getting highs but no peak? Anyone else take a long time to get their peak before AF arrived?