Hi I'm 14 years old. Yesterday i was doing 30 lb flies with a dumbbell, after i stopped working out my shoulder was hurting a bit, i wake up this morning its killing me, can someone tell me what to do please? Thank you.

and what muscles does the "dumbbell shoulders press" exercise benefits?

i'd like to work out my shoulders, back, and chest, but only have 1 dumbbell. What are some good exercises.