I decided to visit a doctor.He examined me and gave me a prescription for an ultrasound.The test revealed the presence of a DVT(Deep Vein Thrombosis,or a blood clot in the leg).I spent a week in the hospital.
One of the main differences between a leg cramp and a DVT,is that you usually "feel" the muscles knot,when you get a cramp.The DVT takes you by surprise.
Smoking(the leading cause of all blood clots)
Being confined in tight spaces too long.
Lying in bed too long or not changing position.
Heavy ingestion of vitamin K(found in green leafy vegetables,green tea,etc).
Lack of an exercise routine(mainly walking).
I'm sure that you could find more.
IF YOU THINK THAT YOU MIGHT HAVE A DVT,LIMIT YOUR WALKING AND HEAD TO THE EMERGENCY ROOM.THE WORST FEAR IS THAT THE CLOT COULD BREAK OFF AND MOVE THROUGHOUT THE BODY.