I have been tightening it with the key as instructed, so I understand it gets tighter, but just now I cleaned it whilst brushing my teeth and on my right side of my mouth at the top it was bleeding, I can feel pressure on that side of the expander, is this right, I am having it in for 6 months because I am 17, I tighten it twice on a monday and friday. I have felt pressure for atleast two weeks. When I go to push it back in sometimes it is stiff and hard to push in.