Need braces again will nhs help???

Hi really urgently need advice/help. I'm 17 turning 18 in a couple of months. Had braces for about 19/20 months when I was 13-15. When I got them off I was given a Hawley wire retainer for my top teeth but no retainer for my bottom teeth. Almost immediately they started to shift but the dentist wouldn't listen to my concerns and I left it thinking I'd be fine . It's been over 2 years I've had them off and my teeth are terrible , a year ago I went back and he said stop wearing your retainer although I continued to do so but now it no longer fits at all, I wore it everyday for about six months when I first got it and nightly up until now but my teeth have a really severe open bite and top two teeth are really potruding and bottom teeth are all messed up aswell. He also shaved one of my teeth that was drifting downwards and it is noticeably smaller than the symmetrical one on the other side. Talking about the tooth next to my top front teeth. I want to complain about this and I really need braces again will I manage to get them on the nhs again . I'm so upset and depressed about this, my orthodontist had retired now so should I speak to my regular dentist about this ?? I had a tongue thrust which my dentist knew about but he still didn't give me the right retainer. Please understand I'm not being dramatic in any way this is not for cosmetic reasons , I have a severe open bite about 5mm and teeth are really potruding. I feel so let down by my dentist, he's ruined my teeth and left me with half a tooth after the shaving so even if I get braces again that will be noticeable. It's ruined my self confidence and my life , is there any chance I will get referred again and if not could anyone recommend any private dentists on Birmingham that are good With braces. Thankyou so much for reading.