Recommendations for online symptoms checkers

I would like some recommendations for an online symptom checker for illness.

I have been getting severe headaches, as in seeing stars and profusely sweating for no real reason.  My Doctor is determined it is only my high blood pressure, but if that were the case I’d have them more often and not when on my meds.

I would like some other options to take to him.  I’ve tried WebMD’s symptom checker and it wasn’t to helpful.