It sounds pretty normal though it's also a question of degree.
A small amount of swelling is normal; a significant amount is not. And the trend is important also. Do you have more swelling than a few weeks ago, less, or the same? The greater the total amount of swelling, and the more it's increasing lately, the higher the likelihood that you are accumulating some fluid. This fluid can be drained off, or drains reinserted, or both but - above all - you don't want to wait too long. The longer the fluid stays there (assuming it is fluid) the more difficult it may be address it ultimately.
So you should contact your PS and explain what's going on, and make sure that everything is healing as it is supposed to be.
I hope that this helps, and good luck,
Dr. E