Hello! i just have a quick question - i have a slightly hard, somewhat tender section of tissue on the palate right above/behind my right upper molar, it's nothing visible, but does feel different between the sides. any idea what it might be?

Something like this would have to be examined, preferably by your dentist. A cyst is a possibility. A hard lump in the midline of the hard palate is often a congenital benign bone growth called torus palatinus.

Any changes in the tissues of the mouth should be shown to your dentist. You may have an unerrupteed wisdom tooth coming in, there might be a gum pocket, or even a root canal problem. Please go and get it checked and x-rayed.