Betta Sinking To The Bottom?

So recently I've noticed that my sweet little betta so longer sleeps in his plant and at the surface, he sleeps on the bottom of the tank. I just thought he was being his quirky little self but today I lifted the top off the tank and he wouldn't even move. I got him to finally move and he was swimming very low to the gravel, looking like he was being pulled down. Does anyone have any ideas what's wrong with him? I don't think he is very old, I got him from a breeder in January. He is a HMPK betta.
He is not pineconing or has rapid breathing. Could it be his swim bladder? Or is he tired or something?

 

My boy does the same thing but has a mass that is weighing him down. Is your boy pooping?

 

I haven't really watched, mabey.

 

Maybe fast him a few days

 

I just looked.. he has dropsy. I'll make a new thread for it and see if anyone has tips so his last days he will be happy. Thanks for the help though