Suggest Treatment For Severe Itching In The Vagina

I hope you can help. I have been having a slight burning feeling in my vagina for about 4 weeks now at first It was accompanied by a fishy smell, severe itching and swollen vagina so I took a thrush tablet then I thought I had bv again as I suffer from this quite often so went to my doctor and she gave me some antibiotics however the swelling and smell have gone but its uncomfortable when I sit down and now I have noticed a slimy-watery gel like metallic smelling discharge. Could I have a sti? please help im so worried