I nursed my son for 2.5 years and had many many colds...I have chronic sinus infections.
Anyway, ibuprofen, breathe-right strips at night, a humidifier or vaporizer, and lots of water help alot. Beyond that I would not go any further than a nose spray. These medications are ok because they are applied locally and thus don't run through your blood stream. You have to use them more often and they aren't as effective, but they do help. That is as far as I would go. Don't take meds that are from Tylenol just cause Tylenol is ok while nursing, you have to look at the back of the packages and make sure there are no decongestants in it cause that dries up your milk, along with your excess mucous.
Good luck...I know how miserable that is!