My advice would be to get a thermostat asap because that is the only way you will have piece of mind with the hot side. IMHO 98 degrees is too hot to have consistently. I am happy that you got it lower. The low 70's is a bit cold also. Until you get the temperatures a little more fixed, I honestly would hold off on feeding. Close your vents in your bedroom if the snake is in your bedroom. I have the vents closed to my snake room so the vents don't cool down my snakes. It works pretty well actually. I always try to keep my coolside between 78 and 81 degrees and my hot side around 90. If you have to wrap part of the tub with a blanket to help keep it warmer, that is an idea also. Good luck.
Star