Just coming off of a shoulder surgery 4 weeks ago myself...Luckily, it didn't involve the rotator cuff...so it's been a faster return.
As stated, do EXACTLY what the doc's tell you, BUT....ask LOTS of questions. They're not used to people who will a) Push through pain b) do MORE than what they're told they're allowed.
5+ years ago with the other shoulder and rotator tears, I kept repeating, "tell me where the line is between pain and damaging my recovery!"
It made a huge difference when it came to "pushing too hard" and having setbacks.
This time, there was less soft tissue damage and repair, mostly bone ground down, so they didn't give it much thought...and I over-did it and got tendonitis. NOW I'm getting PT and it's going better again.
Make sure you know EXACTLY what you can do and do only what you're supposed to...like Daryl Waltrip says on Fox re: racing..."Gotta sometimes slow down to go faster!"