My anxiety is high..

I’ve been receiving faints since 10DPO & today I’m 12DPO. Had a blood test yesterday and my doctor called back to tell my my levels are only a 17.. I really thought they were up there with how dark my lines are now (pee a on a stick aholic) I had a miscarriage in January and I don’t think my lines ever really got this dark.. he wants to retest next week.. should I be worried? I’m so scared to lose this one.. my period isn’t due until next week. Stupid question but does the bottom test look darker than this mornings? I need to take a deep breath 😭