This is totally normal.. this is expected and this will happen with just about any type of athlete or someone that trains.. if it is of any concern to you and if you would like a piece of mind, throw in a few more rest days and do some water loading.. on your off days don't take any supplements, cut back on any whey protein powder or any other type of powder supplements.. just consume natural macros where you can get all the nutrients you need, just rest up and consume plenty of fluids..
I know people hate rest days and I'm one of them, because we feel unproductive especially the way our mindsets are geared, but the fact is that we do need them and they are equally important for our health.. in fact once in awhile I will dip off for a week or so.