After two days of taking Biaxin XL, I feel much better physically...

After two days of taking Biaxin XL, I feel much better physically; the metallic taste in my mouth is tolerable. A possible side effect that concerns me is I've since been experiencing sleeplessness, increased energy and an incredibly good mood (I like the good mood and energy) but is it facilitating a move into a manic phase? (similar to what Prednisone has been known to do) I'm otherwise a healthy person with no hx of depression or any other mental illness. Anyone else experiencing this?