Skin rash all over my body?

Basically today i broke out in a blotchy red skin rash all over my body. The rash made my skin feel really warm and kind of swollen. I've never had a rash like this all over my body although i have gotten it only on my nees once and i also got it on my elbows once. i did start taking the herb St johns wort. I read the side effects and it is possible to get a mild skin rash. Im also awar that there can be drug interactions but im fine because i dont take any drugs or perscription medication. Im not sur if i should stop taking it or not. It has been helping me soo much with depression and i dont want to start taking a perscription instead. Does anyone have any advice?