My frog Bubba had similar problems. I was ignorant of vitamins and minerals which the frog needed. I fed him only crickets. He got sick because I had over saturated his substrate with water. Everything was wrong for the little guy and he got sick and nearly died. I fixed his cage up but he acted like his legs didn't work. For Bubba it seemed like both his front legs were useless. I quickly got some multivitamin dust and calcium with d3, and cut a European Nightcrawler into thirds, put them in a bag with the dust inside, shook it up, and force fed the sick little guy some worm bits. Well, by the next day, he was looking healthier! He was standing up again. And a day after that he was frisky again, able to jump and walk and burrow and struggle when picked up! So I would recommend you get some of that stuff as quick as you can and get some in your frog. I don't know specifically what's wrong with your frog but it sure helped mine. Bowser is a real cutie, I hope he pulls through this! Keep us updated and if Bowser doesn't make it please don't blame yourself, many frogs are improperly cared for at big pet store chains. It doesn't seem like you got a healthy frog to begin with. But it's great that you won't give up on him! I didn't give up on Bubba and now he's growing and healthy and strong. I hope you try your very hardest and Bowser can make it. Thanks for giving Bowser a chance! =)