Hello to you and I hope that you're feeling okay otherwise since your surgery.
Bladder infections can be very normal after such an invasive surgical procedure. Your bladder had to be pushed aside and pushed back again - and it has to go through a healing process of it's own. I never expected to have such pain and pressure in my bladder after surgery; it just wasn't something that was discussed.
Increase your water intake and I still am a big fan of cranberry juice or grape juice for bladder problems.
Since it's only been 6 weeks since you're surgery - i'm thinking that you should start feeling much better within the next 2 weeks.
As for the caffeine; maybe cut down to a half-decaf coffee or drink herbal tea. The caffeine acts as a dilator and could irritate the blood vessels around your bladder.
Let me know how you're feeling soon!
Take care,
lori