Retained products

I had medical management 5 weeks ago. Still been getting very faint positive HPT's so had a scan and blood tests...HCG was 17 on Friday and the same today 48 hours later. The hospital said my lining is still thickened (14mm) but no obvious pregnancy tissue visible. They told me because hormone level is so low and I have no signs of infection they think my body will sort it out on its own when I get a period. This is so frustrating! Been dragging on for 5 weeks already and no sign of it ending. Has anyone else experienced this? Did you have to have any further treatment or did it sort itself out? I really don't want a d and c if I can help it. Just want to try again and getting very frustrated now 😢