my small goldfish sometimes go to the top of the fishbowl and seem to be gulping air...is this normal or an indication of poor oxygen levels or something related

Thanks...thats what I figured.  i just did an full water change and am adding a filter to the fish bowl.  it went from crisp and clear to cloudy in 24 hours and thats when they started to gulp.  hopefully the filter will do the trick.  i also add tetra easybalance with nitraban to all new water before putting the fish in.

More than likely breeding behavior hannah, its that time of year.  If he seems like he is up the other ones butt a lot and like you said nudging then he is probably trying to get the female to release eggs.  If it gets too bad you can float a colander in the tank and put one of them in there to keep him from injuring her but if she seems ok then I would let nature take place and just let them be.  She should release eggs pretty soon.

How big is your tank? The bubble eye wont survive if you don't give it treatment. Put a little bit of aquarium salt in the bubble eye's tank and he would have a better chance of surviving.