I purchased my first ever Helmet, its a HJC rated SA2010 auto race. My question is, Do helmets loosen w/use? I wear a Med.,Yeah I have a compact Melon. This helmet w/ the nomex ninja mask is snug but not uncomfortably tight. I'm not sure if I should return it for a large if its not gonna loosen a little w/use. Some Racer Exp. insight would be appreciated here.TIA.