cannot flex my left Triceps at all

For some reason I cannot, AT ALL, flex my left triceps... dont know why. I had one left shoulder injury once from dumbbell press but thats a few years ago so i dont think thats the reason. BTW my right arm is normal, I can still flex my right triceps.. plz help.... should i go to a doctor?
PS I always workout both of my arms evenly, and no my left arm is not broken at all, just cannot flex my left triceps.
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Agreed. Please seek advice/care from your healthcare provider.

As mentioned this is something we can not advise on and suggest you contact your PCP and talk to them.Closing this thread