Is it normal to cough up mucus after straining your vocal cords? Because at band practice today I was singing really loudly and really high pitched, and I usually don't sing like that.

Will it go away even if I continue to sing like that? Because the band says it was a good voice, and I liked it too. Kind of reminded me of a mix of Axl Rose and Steven Tyler.
No it isn't normal - however milk creates extra mucus so maybe cut down on that and other dairy products a little. Are you sure you've got the right technique?
Before i start to sing i usually put in a lemon in my mouth. Then after that i take some water with a little bit of vodka.
Then the mucus is history.
If you look for the high tones then you should go to a chick, grab her boobs and let her kick you in da groin.