worried b/c HCG levels

Elizabeth • 3 ectopics(2003,2010, 5/2018) 1 m/c (3/2017) no babies :( 35 still trying

Dr's would say I am 5 weeks today but I am really like 4 since I know I ovulated April 13th..weird how they add the time between first day of last period to ovulation...anyhow my first levels were 22 on a Thursday, 60sunday and 98 tuesday ( yesterday) ..my Dr said those are low and I worry each day I'll miscarry. I just woke up sick and when I do I am happy as I hope my levels are rising..anyone have same situation?