Help. I took 4 Advil (200mg) 2 days before my breast reduction surgery. Am I going to have to postpone my surgery?

No, you're fine, if your surgeon who knows your entire medical history agrees.  The use of advil (ibuprofen), while not desirable, will not increase your risk of bleeding in the time frame you describe.  Platelet function returns to normal 24 hours after taking ibuprofen.  This does not apply for all NSAIDS, since piroxicam, diclofenac, naproxen and indomethacin inhibit platelet function for 2-3 days.
These drugs reversibly inhibit platelet function and the effect wears off as they are cleared from circulation.  Aspirin on the other hand irreversibly inhibits platelet function for the life of the platelet, so aspirin should not be taken within a week or surgery, and I recommend not taking it for 2 weeks before and after.

You need to ask your surgeon about this.  I would be much more concerned if it were aspirin with a facelift.  It would be best to delay the surgery a few days if you can.  Just make sure you discuss this with your surgeon 

Personally, I don't think its a big deal to take Advil prior to cosmetic breast surgery - but certainly contact your surgeon to ask him/her yourself.