I think my snake is in the beginning faze of shedding as I noticed its eye color is changing.

I have been feeding it on Wednesdays so should I go ahead and feed or should I wait?

I have a 20 gallon fish tank I'm using and can not get the humidity above 40%. Right now it is 38% but it is usually around 40. I have 2 water bowls in it now and I also put in a wet wash cloth in. I am using a 50 watt heat lamp and the temp on one side is 90 and 79 on the other. The betting is shredded wood chips. Any help would be greatly appreciated.