My car was recently in an accident and after getting it back from the shop, at night when I want to turn on my low-beam headlights the high-beam headlights turn on instead so I have to drive with the high-beam lights which really annoys the drivers on the other side of the road or just drive with no headlights at all.

Anyway easy way to fix this myself or do I have to take it to the shop again?

take it back to the shop. They f***ed it up. Make them fix it.