Is it a breast implant infection?

It sounds like you have some breast wounds however it is difficult to determine if there is an infection present without an examination or photos.  I would recommend following the instructions of your surgeon and keeping all appointments.  If the infection worsens, see your doctor right away.  

The description of redness and warmth combined with fluid leakage is concerning. That being said, your surgeon placed you on antibiotics and is monitoring your recovery appropriately. Work closely with your surgeon and follow their directions. Your surgeon is in the best position to help you recover appropriately.Good Luck!

It's difficult to say without photos or without seeing you.  Sounds like you might have a spitting suture and it may be getting infected.  Keep a close eye on it and keep in contact with your surgeon and follow his instructions. ac 

so its best that you continue to trust your surgeon who should have a vested interest in you having the absolute best results possible.  If you have good soft tissue coverage of your implants, the superficial things on the skin should not affect your outcome.

It sounds like your dissolving sutures are getting irritated and infected.  The treatment for this is removal and sometimes antibiotics like your doctor is doing.  Some people have this problem while others are never bothered at all.  If you develop more areas, go immediately, seek help with your doctor.