The highest I ever saw was 196 (running up a hill) so I'd say that yours is fairy normal. The only thing to watch is if you have (or think you have, or have very recently had) a cold or 'flu virus, as some of these can muck about with the heart rate to the extent that you hit MHR much sooner than normal and you think you are about to die. If this happens, keep riding slowly or get off the bike and sit or lie on the ground. Otherwise, as soon as you stop, all the blood pools in your legs and you faint. Fainting itself is not harmful but whacking your head on the ground while unconscious, and therefore unable to break the fall, is very painful. DAHIKT.
I also hit MHR halfway through a flat TT once...I vaguely thought dying on a flat road would make me look a bit of a lightweight as I slowed right down (following the advice above). 30 seconds later everything had dropped back to normal and I could get back up to race pace again. It's scary when you can't breathe, though.