Weird Health Problem (+rep) Help pls :(

So i had this very weird problem. Whenever i get nervous or i use my legs too much like standing up or running , i'll start twitching. My hands , legs and mouth will twitch for like a few seconds. It's not painful at all. But it just keeps twitching. I had this problem for like 2 years. It's happening frequently since last december. I've consult all the specialist and did lots of scanning test such as MRI and whatever i forgot what it is. I even took pills. Last time i took the pills given from one of the doctors and i vomit for like a few days and got a very high fever. So i stopped taking pills as it's only make the situation more worse. There's once this thing makes my muscles cramp for 10 minutes. And sometimes i twitch infront of my friends , family, and also my teacher. I look horrible and very ugly when im twitching. Sometimes i even fall down on the floor when it got worse.

Anybody can help me out i'm appreciate it :'(

+ rep for useful advice.

I get mild twitches from time to time but thats because I had a mild stroke when I was 8... Apparently its just muscles doing what they do... ik it makes no sense but that's what i was told by a doctor

I don't really know what could be causing it. The only time I've ever started twitching was when I overdosed on hayfever medication by accident and it was one of the side effects. But I know that mini seizures can have a similar effect, as well as epilepsy, and like Lemar said, mild strokes. I would probably go and see a specialist again, and see if further testing could be done, or to see if you can be given different medication if the ones you have are causing such an adverse reaction.