Workouts affecting Menstration

It is often normal, but it can also be a sign that there's an imbalance somewhere, such as too little intake. I would check with your doc just to make sure there's nothing amiss.

I know that women who work out too much will stop getting their period all together (like Olympic gymnasts. This is why it's such a big deal if they break something--once your period stops, your estrogen levels drop and your bones become brittle and don't heal well.) I'd say if your period is absent, taking more than 14 days, or they are really close together or too far apart, see your doctor. Otherwise, I'd just stick to your new healthier lifestyle and it should work itself out with time.

It depends on what you mean by "crazier"- from working out they should be less painful (if you normally get cramps) and also get a little lighter. I would definitely talk to you doctor if it's getting worse than normal.

It makes sense if you think about it. Periods are regulated by hormones, and hormones are composed of lipids (fat). So with a loss of fat, the body's hormone balance will fluctuate for a while until it figures out how to more efficiently use the lipids (which before had been in plentiful supply).