Hyperactive Dog, Cant Train Him, Could Have Mental Issues?

i rescued and adopted a dog 4 months back, first he had seperation anxiety then he got over it, but he is just toooooo hyperactive, never gets tired, he plays with his rubber ball all by himself, takes it tosses in the air then catches it. He will be on the couch playing with the ball and it will fall on the floor 100times and 100times he will pick it up and make it fall the same way.
When i want to take him out for a walk as soon as he sees me taking the leash he gets so excited, so hyperactive he starts making these squeeking noises and just goes crazy. he doesnt listen to me, when he is on a leash he pulls like crazy and keeps going left and right, sometimes he has accidents in the house even though he knows where he has to go.
if i am walking him and he sees a child he goes crazy and starts barking like mad. when i come home from work my other dog greets me normally, wagging her tail and all happy but he, he goes jumping in my mouth, jumping alll over me, trying to knock me over, just jumping like mad.
i want to calm him down, train him but its impossible, cant afford a trainer atm but id like to know what i can do to calm him down (no medications) and why is he acting like this, is it normal or is there some mental issues?my other dog does not act like this at all. he is a very loving dog and i love him to bits but id like to calm him down especially when ppl come over.
btw he is a papillon, about 1.7yrs old