What can be done to correct this. They are under the pectoral muscle and uneven?

The synptoms you are having may indicate an infection or something worse.  It would be best for you to be seen by a plastic surgeon who does breast reconstruction.  Otherwise get yourself to the emergency room to be evaluated.

No, generally it is not common to get a blister after expansion. A blister could represent underlying tissue necrosis and it is best to meet with your plastic surgeon.

Yes, cigarettes can impact surgery even if you smoke occasionally and a few weeks before surgery. Best to review with your surgeon.

This is an example where a photograph would be very helpful. I'm not quite sure what you mean in your question. We do try to avoid doing breast lifts on radiated breasts. Fat graft can be helpful to add some volume but not large volume changes, at least in one surgery. Please resubmit

It's not uncommon to feel cold after implant-based breast reconstruction.  The implants can act as a heat sink, and on the chest this can be particularly noticeable.  The anatomic "gummy bear" implants may cause this phenomenon more than the round silicone type.  Speak with your surgeon about wh...

Thank you for your question.  Indeed, your surgeon is right.  800cc is the largest silicone breast implant on the market.