i have been having muscle twitching in my thigh and
Considering your age, it is unlikely to be serious, needs evaluation.
Welcome to Ask A Doctor Service.
I have gone through your query and understand your concern.
Isolated Muscle twitches are usually benign and do not require much of an attention.
However, if the persist and continue to bother you, then you must get yourself examined by a neurologist to rule out motor neuron disease like ALS or MS.
If you have had too much of coffee in the last two days, or if consumed caffeine containing energy drinks such as Redbul, then you can expect to have such muscular twitches.
Take plenty of liquids, avoid caffeinated drinks, get adequate rest.
If you see a persistence of these muscle twitches then you must visit your neurologist.
I hope I have been of some help to you.