I dont think there is anything to be worried about Lisa
I would however think about a play mate for him (i know you were talking about that some weeks ago). Some single cats can get very lonely, it wouldnt have to be another Pred - I would just go for a moggie kitten.
Also his hormoans will be starting to kick in now too - I would get him "done" as soon as poss
failing that - the offer of him coming to live here is still open
(well i gotta keep trying
)