Please help :(

Madelon

So 6 months ago I gave birth 6 weeks after I had her I got the mirena in my obgyn basically forced me too said it was ‘amazing’ immediately after having it in I felt terrible had horrible symptoms I only had it in maybe 2 months if that and had then had it removed. After that I noticed my vagina has not stopped itching and just not felt right and smells. I have had a vaginal swab which was normal no bacterial infections and also tested for STD’s which all came back negative I’ve also taken the yeast infection cream and tablet which didn’t help. I’ve been using a steroid cream which doesn’t help either. What could it possibly be I am so over it. I had a ultrasound done too which seemed fine al they found was some free fluid in my ‘pouch of douglas’ but didn’t explain anything which mustn’t be serious ? Can anyone please tell me if they’ve been in the same situation and what it could be ? Thank you :’(