You probably have some significant imbalances. I would suggest this for starters.
Remember that it is not about weight moved, but targeting the muscles.
Start out very light, stay light for a while, just basically going through the motions, then slowly progress up. Stay in the higher rep ranges.
I have used this very successfully and cycle it in and out all year, particularly in the weeks before starting a meet cycle. It helps alot.
Also, do a search for the "Lazy Man's Guide to Stretching." It is pretty thorough and the stretches are easy to do correctly.
Placing some emphasis on rear delt work and upper back would probably be beneficial, as well.
You might want to consider lowering the total volume of pressing movements for a while, as well, and having a bias towards pulling. 6-8 weeks while you progress through the shoulder routine.