I'm 3 weeks post inguinal hernia repair. I still feel discomfort, sensitivity and restricted mobility. Is this inflammation?

Based on your question, it looks as though you had an open inguinal hernia repair with a single incision. Standard healing time for a hernia repair is 6 - 8 weeks regardless of how the hernia was repaired. Several factors can influence your recovery and method of repair is probably the largest single factor. If no mesh was used, then I would expect you to be feeling a bit better at this point but it depends on how big the hernia was to begin with. If mesh was placed then you could have some prolonged inflammation as mesh promotes inflammation. Either way, I would expect the site to continue to heal. If you aren't feeling significantly better in the next 1 to 2 weeks, then I recommend you return to your surgeon.

some discomfort is normal, but if its not improving, or getting worse, then certainly needs to be evaluated.  i'd recommend following up with your surgeon so he can evaluate your post-surgical symptoms