Implants downsize

Dear Dr. Pinsky, please help. I have 28″ ribcage,preops 32A now 32D.380cc Sientra round mod. they are too wide,I can feel the left implant under my armpit. Will they move to the front after healing? I am in 5 weeks post ops. If I want to down size to 270-300, when is the best time to have revision? Do I need internal suture for smaller implants? Is it dangerous,how long will I completely feel normal? What risk do I take? I am sure I hate this size. I understand I still have swelling but they will not decreased much than now after all.