When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Well, you're drawing more than 50% more amperage than the design load. In order to save cost and weight, nobody overdesigns anymore. It seems likely that you are shortening the life of some parts of the circuit. However, if you're not tripping circuit breakers (headlights would flash off and on), you might get away with it.
I would probably rewire using a relay, but you still could be damaging the plug and reflector assembly by the extra heat. Also, your existing optics may not be correct when the bulb is brighter (hence the "blinding" complaint). If you really need more light, it's far better to get auxiliary lights.