Welcome to HCM
First of all you haven't mentioned the medicine prescribed by you doctor. If its normal NSAIDs like diclofenic sodium or diclofenic potassium then there are certain other options for pain killer which you can use. These includes Tramadol, peroxicam, meloxicam
, hyosine compounds, codeine compounds and if all these fails, then you can go for neurotransmitter
blocking agents like carbamazepine
All these drugs are on the counter available drugs however i will recommend you to consult your doctor once again for the current issue before any self administration of the medicines.