Front bumper not sitting flush with headlights

[Nyall]

Okay, so I fitted some new bulbs yesterday, and to gain more access I took off the top headlight bolt and gave the headlight a little tug to give me a bit more room behind the headlamp.

However, I now have a gap between the headlamps and bumper. Anyway to fix this?

Will upload some pics soon to give you guys an idea of the gap