i live in ontario too, the weather has been crazy lately. however, when i got my shot i felt kind of drained too and i was on a low dose and weekly shots. it does get better though, i think it was just the shift in hormones. if your doctor started you off on what is considered a "normal" dose, it could be a big shock to your body. as someone else said, talk to your doctor about it. if you get headaches or dizzy, you should see your doctor asap.