It's a small cyst, the vet was able to drain a little from it, gave me some Quadritop Ointment (Nystatin-Neomycin Sulfate-Thiostrepton-Triamcinolone Acetonide Ointment) to apply twice a day. I'm also going to try damp warm compress to see if that helps. The vet said it could be from a puncture wound, insect bit (no bitable insects in viv) then just said not sure. Poor toad.