You need to set up an appointment with a therapist/psychologist so you can discuss these urges and idealisation to harm or kill yourself. What you are describing may be an obsessive, intrusive thought pattern that can easily be solved by speaking to someone and going on the right medication (even if only for a temporary time). And there are medications that are deemed safe to take while pregnant if you are worried about that.

I hope you get the help you need!

Sorry that you're having difficulty getting what you deserve through NHS. : S