Hi Betta,
That's an interesting question that I think alot of us get. I researched the topic a bit and came up with this:
Night-time stuffiness moves to whichever side of your head is on your pillow if you are lying on your side. Gravity drains the congestion to the lower side. This condition goes along with postnasal drip and, often, a constantly runny nose. This is worsened further by the head-forward posture and congestion of normal fluid passages caused by TrPs. Check for a TrP slightly above the outer edge of your upper lip and toward your ear. This TrP is a cutaneous facial muscle, the sygomaticus major, and it can add to sinus pain. It may also cause a restriction of serveral inches of your jaw opening.
A small massager in the sinus areas helps to loosen thick mucus and promotes a sneeze. You can cleanse your throat and nasopharyngeal area using very warm salt water as a nose wash. Try doing this procedure just before bedtime. If you suspect the area is raw, use less salt and a lower temperature for the water. (Use about 1/2 cup of water and add one gentle shake of salt). Lean your head back as far as you can and use a dropper with a small amount of the salt-water mixture. Insert the dropper inside your nostril, with your head bent back as far as you can. Rinse the lining of your nose with the dropper pressed againts the top of the inside of the nostril. Then spit out the water and blow your nose gently. Repeat the process in the other nostril, then repeat each side with the dropper pressed against the bottom of the inside of the nostrils.
Gargling with salt water may also help clear away thick secretions and prevent further irritation. If you do this procedure every night before going to bed, you may find your nose and throat becomes less sensitive to the salt and the temperature. DO NOT use the massager or salt-water nose drops if you suspect an infection, since you don't want to spread the germs.
As for the roof of the mouth swelling, trouble with swallowing may develop due to the presence of digastric TrPs. This leads to head and neck pain and a "swollen glands" feeling. Researchers confirmed that their patients with facial pain and abnormal swallowing had digastric hyperactivity in every case. It hurts to work digastric TrPs! Start with warm, moist packs on your throat for a few minutes. Then put your elbows on the table and rest your thumbs on either side of your jaw, under your chin. You are trying to get a release of the myofacia, by "milking" away excess fluid. Use a gentle backwards motion from the base of your chin, stroking or pressing up to the base of your ear. Start gently and listen to your body. It will tell you how much pressure to use. Gentle bodywork may help you to deal with these TrPs.