were you feeling on his nipples?!?!?!?
im not a doc, so take everything i say with a spoonfull of salt, it sounds like psuedo-gyno to me the classic gyno around here is definaly lumpy and hard. the lumps feel like little beans in a bean bag almost.
before anyhing else, id say take the time to diet down for a month or 2. do it hard, cause you really want to know the nature of the beast. then, if things dont clear up, look above for a possible option. or you could goto a good doc, and have him ID it.