anyone experience after an intense workout you get muscle cramps and spasms?

this happened to me, after a long workout where I was really trying to fry the muscles.
later that evening I began having involuntary muscle spasms, twitching and cramps. Really strong spasms, this lasted for hours.
post workout I had a protein shake, some BCAA tabs, and small piece of cinnamon roll (figured my body need a bit of sugar and carbs, or else i couln't fall asleep)

my question: is that a general good indicator that I accomplished my goal to fry the body parts I was training?

would restricitng carbs at that time force my metabolism to burn off body fat for energy?