Heat Setup

Hi, my girl is not eating that much right now and she's sticking to one of her hides a lot more than normal. I think it's because I live in southern VA and it's getting a lot colder. She has a very big tank (33 gallons, she came to me in a 10 gallon and I wanted to give her the world lmao) and she has both a heat lamp and a heating pad under one side of the tank. I have a thermometer on the heat lamp side and it definitely needs to be hotter for her. I think since it's such a big tank I either need a stronger lamp or a second bulb. Her current bulb is 75W and was working fine when the weather was warmer but has definitely dropped in quality since the temperature here dropped. I'm mostly looking for heat setup recommendations but any advice would be appreciated!!