I would say no if you used them that much
however pigments are packed according to weight not to the top of the bottle some will have less and some will be briming and full, so depending upon which one it is, thats just the way it is. that is of course if your talking about how much was in it when you bought it.
if it was that full when you bought it.. and well you really dont like it, its up to you if you want to return it or not.