First beam light flickering

mine did this, and it turned out to be a melted ballast connect/bulb hold. Have a look in the headlight from the front and see theres any smoke in there, mine smelt smoky too
 
yeh seriously, i changed the side lights over a week or so before, and i think i must have upset it, as it was quite awkward to get them to fit. if it doesnt look smoky in there, or smell, then my guess is that it should be ok

what i would do, would be take the whole headlight out, and check it over