I just dealt with a bad back / Muscles .. Ice is good! …I once pulled some muscles in my neck/shoulder area … i thought i was doing well putting heat, it brought temporary relief, but after ending up at the doctor, He said no heat at all for the first 48/72 hours.
he said while temporary relief, i was only inflaming the muscles .. (kinda like when posters respond to TA/Day traders comments) only inflames the situation.
ICE is your friend, I had shooting pain that was unbearable !! .. muscle relaxers and pain meds did nothing!
I would ice it till the pain went away, then repeat .. be careful not to burn your skin with a direct ice pack.
hope you feel better, Mr.Bug