I hadnt worked out in forever and just got back in the gym and wouldnt you know i tried to do what i used to be able to do and the 1st day i hurt something. 1st mistake i suppose.
I dont know what the proper name is but i heard someone call them head-busters(holding a hex bumb-bell behind your head w/both hands and lowering it between your shoulder blades and then extending your arms upwards) one time so thats all I have to go on.
So anyways, i woke up the next morning not in terrible pain but i cant flex it as much as i need to for my job. I have full range of motion with my arm and can fully extend my arm but i can only go so far when i try to touch my R shoulder with my R arm. Starting in the 90 degree position i can only make it about 30% of the way before I start feeling resistance...about 50%-55% max.
Does this sound like a pull or a strain and whats the difference?
This happened two days ago and it has just now gotten to the point of me feeling like i need to put some ice on it. What do y'all suggest?

I suggest avoiding use as much as possible, and doing a warmup next time. It shouldn't hurt more than 4-5 days for a pulled muscle, if it still does you might want to get it checked out.

will do thanks.