You may be lacking in any or all of these: magnesium, calcium and potassium.
Make sure that you drink plenty of water so that you do not become dehydrated and try a supplement of magnesium and take as directed on the packet.
If you start the Magnesium, start at 400 mg once a day or it may give you diarrhea and bloating. Also take it an hour before bedtime. Calcium comes in 2 forms; either is fine. Potassium you usually need a prescription for, but it is best to have a blood test done because too much or too little can affect your heart and kidneys. I suggest you see your doctor to be worked up and have lab work done.
Bananas are full of potassium.
This is true about bananas, however if someone is severely deficient in potassium, they very often require supplements which need a doctor's prescription.
Prior to starting any of these supplements or changing your diet, I would suggest that you see your doctor to be evaluated and have blood work done. If you make changes and start taking supplements and change your diet before this, your doctor will not have a baseline of were you were when you started having the symptoms. So please call you doctor and make an appt.