Terrible Itching and Blisters

Am needing some advice.. I've been getting really bad itching that started at my neck area. It gradually moved from my neck to my chest onto my breast, it's really red and developed a rash that just won't stop itching. I got up this morning to see that the rash is now on my nose and it's causing blisters on the outside and inside of my nose. Am so uncomfortable and am not sure what to do or maybe what's causing this.

Anybody went through this? What should I do?

Am currently 37 + 4 weeks.