HCG level

Hello, I just recently found out that I am pregnant (4 weeks, 5 days) I am 3 days late for my period. I ovulated around day 17-18 of my 30 day cycle. I had a beta HCG done today and it was 87. Its within the normal range but I'm still worried it's too low. Can you tell me your hcg levels around 4-5 weeks?