PLEASE HELP. Health question regarding my orphaned baby opossume, who is now 2 years old.

This morning my 2 yr. old domestic pet opossume was not responding like his sweet, normal, happy to see me self. As the afternoon and evening passes his health is getting much worse. Due to Missouri laws, taking him to the vets office is out of the question. His symptoms are as follows:
involuntry hind leg stiffness for a few seconds, kinda like contractions....
Rapid shallow breathing, NO interest in food or water, lathargic and his body seems to be kinda stiff and cool. I beg someone to help me, I just love him and Im not sure what to do to help him. PLEASE HELP ASAP!
Asked Sep 19, 2013

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