Hi there, I had a band 4wks ago and I too couldn't believe the post op pain!
It took me a week to feel human (although the pain did lessen each day) and I still had wind pain for two weeks!
Even now, at four weeks on my port is still tender, especially when I bend - have seen my provider and this is normal by all accounts.
Stick with it, keep walking and do take regular pain relief (remember to drink lots tough as. Some forms of analgesia causes constipation)
Oh and take care ;-)