New bulbs should be 'burnt' in. Turn it on and leave it on for at least a couple of hours. 10K should be bright white.

MH bulbs need time to warm up every time they come on. It is a good idea to always run them for an extended period of time every time you turn them on (1 hour or more). You will shorten the lifespan of the bulb if you allow the power to cycle on the bulb, i.e. turning it on and off or power loss/fluctuation.

You did not hurt your new bulb but let it burn in before you put it in service.