How to help sore muscles?

So I'm 13 and I took a year off of competitive softball and I'm trying out for new team this year and last night I had a long try out and now my back and shoulders hurt because because I haven't been practicing that much and today in like six hours I have another try out for a different team and I'm scared I might not do good because my back kind of hurts I know this is kind of a stupid question but is there a way to make it stop hurting yesterday I took a bath in hot water and Epsom salt. does that help?
How to help sore muscles?
Post Opinion