Never heard of anybody's tongue resting at the roof of the mouth, you have to physically place it there. Otherwise, there would be no need for the nurse to tell you to place the thermometer UNDER your tongue, she could just stick it in there! If you're not producing enough saliva, there is a medical reason, and this needs to be addressed also. So, please let us know what you find out.
After seeing a physician, if no results come out, you may need to see an oral medicine specialist who is specialized in salivary gland pathology. If there is a salivary research institute in UK, it's probably the best place you can get help.In the mean time, you can use artificial saliva or saliva substitute to relieve your symptoms. There are many brands in the market, which are generally OTC. Your tongue position is normal.
You are not being paranoid, your tongue should rest on the bottom of your mouth. As I said, my husband had Type II Diabetes and he often wakes at night to find his tongue stuck to the roof of his mouth, and also at times during the day.
Thanks for your response and I am going to see a GP tomorrow. One question to people though, where does your tongue rest when in your mouth? I feel my tongue on the top of my mouth and even when I drink it feels like it is sucked up there. Not sure if I am being paranoid or if this is where you tongue is suppose to rest.
Have you been checked for diabetes? These are both big major symtoms of it. Make a doctor's appt. to get checked, but in the meantime go to your drugstore and get some Keatone Strips (I may have spelled this wrong). You urinate on one, and compare it to a chart that comes with them, and the color the stick turns tells if you have diabtes. They come in a small jar and are plastic strips. This is how my husband found out, plus he was never seen without a bottle of water in his hand. I asked if he was actually thirsty, or just liked the water, and he said he was always thirsty. If you have trouble finding them, just ask the pharmacist.