DISNEYWORLD - bad idea?!?

We have a trip planned for the end of August, which is like one of the hottest times of year in Florida 🙃 we planned this trip almost a year ago and our daughter is BEYOND excited. Asks me every day when we are going/how long until we go! I just found out I’m pregnant after years of trying. It was super unexpected because we thought we wouldn’t be able to conceive without medical intervention (what we were told) I am super excited! Just a little concerned because it will be a LOT of walking and heat. I will be just entering the second trimester, so I won’t have a big belly yet. But I’m not in great shape so I’m afraid it will take a toll on me 😫😰 anyone have any advice or have done something similar while pregnant!? Am I overthinking this??