Yes, it makes sese. Problem is probably the chrono cam. It could have come lose in which case you should hear something when you shake the watch. If not the cam is probably jammed. Just open it up to see what is going on. Post a macro pic and I will try to help you further.
Use this to unscrew the case back , I don't know the proper English term
You should have posted this in the 'repair and upgrade' section. You will probably get more usefull response threre. Shoot a PM to a Mod and ask if they will move it there.