My 4 month old guinea pig has a puncture wound just below his ear. Today is was quite pusy. I have squeezed it out and put some tea tree oil dream on it. Anything else I could do? He seems quiet alert and happy for cuddles but I am worried. I have separated him from his two cage mates. Do you think one of them may have bitten him? He is always on his own and I suspect the other two boys don't like him much. I don't know how else it could have happened? (and this isn't the first time either :-( )