A Few Days Ago I Did Boxercise An Exercise I

a few days ago i did boxercise an exercise i haven't did in over a year however i have been doing other exercises, this was th first contact exercise in quite a while. approx 15/20 mins following exercise I noticed my hand trembling quite a lot. this did not fully subside for a min of 48 hours afterward. I went to my GP approx 30 hours after the trembling began. in the past few months I had noticed small issues. On a few different occasions I noticed I stammered my speech a little and on a few occasions my breath went like i forgot to swallow my saliva. I have had blood tests which have came back clear and I hoping to have an MRI tomorrow. I have no obvious symptoms at the moment.