How am I supposed to go out in this tomorrow (Tuesday)?

The hospital test isn’t cancelled but I am unsure how I can stick the peak heat tomorrow (well today now). I walked outside just to my car to go to get food yesterday (Monday) at nearly 7pm and even that heat hit me like a ton of bricks when I got outside. That was only 34 degrees. It is going to be 38 degrees when I go to hospital ultrasound test tomorrow. I have at least half an hour drive to the hospital. It isn’t at the local one like my previous ultrasound. I don’t want my car to overheat due to city traffic. I have air conditioning in the car so that isn’t too bad. It is just getting in and out of the heat. I have never felt the kind of heat which hit me yesterday and that was in the evening after it got cooler. I have waited for months to get this test as part of the investigations to see what is causing my monthly issues. I can’t cancel it because I will have to wait for another slot. I also have to work the dates around when I will and won’t be on. The next slot that comes up may not be on the right date. I’m torn so badly because the weather made me sick yesterday before I even went outside. The pressure in the air affected me. That is what happens to me. I get a headache which goes away after I am sick. I call it my stress reliever switch. I literally feel better after that happens ever so often. That won’t last if the air pressure is quite high today. This is what makes UK heat different from abroad. We are also surrounded by water being an island so the humidity builds from the coast inwards. I’m in the midlands which is far enough from the coast to build pressure and humidity. That is also why london is getting particularly roasted during the heatwave because they’re also situated in the middle. It also gets hotter by a percentage as you go south. That means those parts had a higher starting point before heatwave hit. We don’t have the land area to spread out higher temperatures. Most places that are hot abroad are part of larger continents. I am no snow flake. I will walk in most weathers but even the evening temperature was like being smacked in the face yesterday. If people are frying eggs in saucepans just using the sun then it must be cooking us too.