Am just 16 yrs old now.

I have a problem for many yrs(3 or 4 yrs) now.I got a swelling and pain on my knees(legs),hand pain etc.
mainly swelling can be seen when i wake up morning and at nights and even aftr an aftrnoon nun.
I have been diagnosed and nothing was found and not even an arthritis.
Someone said me that if you find ur legs swelled up when you wake up in the morning and gets lessened aftr a 1 or 2 hrs,it means that you got some heart failure..whenever i get tensed or sad,excited etc my hands and legs get colder..I got those symptoms and am afraid is that true and whether am a heart patient....
pls gimme replies abt this..
thank you.

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