Yes, Daisy, best not to take much notice of the weeing thing. He could just be being lazy and it might not be anything to do with the impending birth - we are always looking for reasons to panic and compensate - don't you just love maternal guilt?
My DS was weeing in the bin for some unfathomable reason (the bathroom bin, next to the loo!). He is Mr Anal, always washes his hands, won't eat after cleaning his teeth, is a germ-freak, but did this odd thing. My cleaner told me about it (see how often I empty my own bins ), and I was horrified. I thought it was DD emptying her potty out, but he said it was him. It wasn't a one off - happened for about 3 weeks. I thought the smell was just having 3 boys with crap aims in the house.