I wouldn't worry about it. 4.5 is normal for a change with filter.
I just had mine done at a shop and they dumped 5.5l of oil in it. :x
Blew the excess out the back of the valve cover, and so far, I don't think the engine is any worse for it, seems to be running OK, but I'm keeping a vigilant eye and ear on it.
Woops, I just realized you said quarts. I'm not sure, how much is that in liters?