Should I redo cheek implants with smaller size? I'm 3 wks post op, look abnormal and exaggerated, especially right one

At 3 weeks after placement of cheek implants, there would still be some swelling present that would affect the appearance of your face.  I would recommend waiting a longer period of time before deciding if you would like a smaller size or not.  It may be several months before you can judge the true appearance. 

Cheek augmentation with silicone implants are a good options for some patients, especially those who want to avoid synthetic fillers. Swelling is common after any facial surgery, and often the cheek implants look "too big" immediately after plastic surgery. Three weeks is still early, and your surgeon will likely suggest waiting several months to allow swelling to resolve before considering changing the implant size.Best,Dr. Chaboki

It is too early to judge the final size and shape outcome from your cheek implant surgery. It takes a full three months to have all the swelling go down and adjust to the new look. Be very careful about jumping back into surgery too soon when the final results are not yet seen.

  I have performed many cheek augmentations, with cheek implants, for over 25 years.  Without photos of your face before and after the cheek implant surgery, there's no way to evaluate size, shape and placement of the cheek implants...all of which affect the aesthetic outcome.  Three weeks is too early, in general, to make a decision on the final outcome.  Based upon the experience of the plastic & cosmetic surgeon performing the cheek implant surgery, swelling can last up to 3-4 months.    The majority, of that swelling however resolves within 4-6 weeks.  I can also say that in my humble opinion, cheeks implants that are too thick or laterally placed can give the results that you are mentioning, however it's best to wait and see what you look like after the swelling subsides.  The tissues would be quite swollen and stiff at this point from the previous surgery and no matter if (and I do say if) they should be replaced, it wouldn't be done for a couple more months anyway until the tissues are healed.  It's best for you to take a deep breath and let yourself heal.  Hope this helps.