First, welcome to the forums, rovers95!

That seems quite counter-intuitive. Huh. You'd think it would interfere with sleep. Well, you know, for one thing. Seems like playing with fire.

Two things came to mind. One, are you now on a mood stabilizer? If not, I'd approach with considerable caution, as you can attest to negative outcome without one. Two, are you in the northern hemisphere? I've not heard of people using light boxes in summer, as they're used to used to combat the extra darkness of winter. Just wondering.