Monica,

Keep in mind I'm not a vet, but have experience with Tramadol, Rimadyl and weak doggie stomachs!  The tramadol should NOT cause any stomach problems.  It's a non-opium pain pill and is very mild.  I personally would give as much as the vet says so your Vinnie can rest comfortably especially since he isn't taking anything for the inflammation (Derramax).  

Everything that has been cut inside Vinnie is sore and swollen and needs time to heal.  (the Derramax was prescribed to reduce the swelling and inflammation)  It will heal on it's own without it – it just isn't as comfortable.  The tramadol won't do anything for the healing but it blocks out the pain signal to the brain.  It will just make him comfy. 

Hopefully someone else here can talk to you about the possibility of phantom leg pain. 

But honestly, he sounds like he is doing great – a major surgery takes a lot of time to heal.  Even with people surgeries, usually it takes a while just to get rid of the anesthesia out of your system, not even counting the healing process.

There's a lot of stuff going on in his body right now and as long as he seems to be improving a tiny bit daily and the wound looks good.  I would just do what you are doing and be Nurse Mom for a little longer!

But for sure, I give him as much tramadol as prescibed.  They really are so mild.  And keep giving him Pepcid if his tummy hurts – that for sure isnt going to hurt him.