Feeling the need to apologise for your childs behaviour

We went to a Birthday party this afternoon, it was the 2nd birthday of the little boy I nanny for at my bosses house .  My,  E , (5yr 9m) got quite hyper and excitable there- they were all crawling around under the big dining room table and he was pulling M's feet  (who I look after), trying to pull him along like he would to O at home and I could see M's dad wasn't happy about it so I shouted for him to stop. Then he bounced on M's dad legs and I had to tell him to stop, he was just generally being silly until I told him he had to leave the dining room and play in the kitchen where we were instead.  

So it wasn't 'bad' behaviour as such but more silliness- probably annoying if its not your child-  but because it was at my bosses house I feel a bit funny about it and feel like maybe I should apologise.  I don't think they understand that 5 year olds can be like that but even so I feel a bit awkward about it. What do you think? Should I make  a comment along the lines of "he had a lovely time, sorry he was a bit over excited"  or not say anything at all? If it was friends I wouldn't give it another thought, but like I said I feel awkward because its my boss!