I'm not pregnant at the moment, but yeah I do remember those bursts of energy, where I'd 'nest' like crazy, demanding dh move the furniture around yet again while I marched around like some sort of drill sergeant.

If you're breathless, weak and dizzy - those could be just normal pregnancy things, but they're also symptoms of low iron, and it's important to have your iron levels looking healthy in late pregnancy. I'd suggest asking for a blood test to check them soon.