I speak ridiculously quietly due to anxiety issues. Could i get speech therapy to help?

I had selective mutism when I was little and when i was 15-18 I had agoraphobia and I am now 23 and still have anxiety. Because of this my voice is REALLY quiet to the point where my family shout at me angrily because they are fed up with saying "pardon?" and "what?" every time i speak. I have started to barely speak around them as it stops me getting shouted at. Also I love to sing but can also only sing quietly, like i am singing under my breath, except from when I know that my housemates are away then I can sing louder. not loud but definitely louder than when they are home. I also have mild learning disabilities such as ASD and Dyslexia.

I live in wales and was wondering if i could get speech therapy? Maybe on the NHS? I had it when I had selective mutism when I was 4-6 and that helped me then.

Thanks xxxx