Jackson's are prone to temporal gland infections. They are located in the corners of the mouth. That is a possibility. Yes on the vet absolutely. Nothing any home remedy is going to be able to fix if you see green stuff coming out. It could be mouth rot also. Pics would be helpful, but sounds like you are still gonna need to get your chameleon to a vet.
I'd call the vet asapppppppppp that doesn't even look right.
I feel so bad for her I adoptits ed her a few weeks ago somebody told me it was a calcium deficiency & to dust all her food & I have but it got worse. It was nothing I did but I feel horrible. This poor chameleon has gone through so much for only being a year old