Is this Fatigue?

I hit a wall of tiredness this afternoon and literally walked directly to my bed after the school run. I didn't manage to rest much and still feel really yucky. Like everything is humming in my body. I am absolutely wiped out. I am wondering whether anyone gets the same as me and that is your heart pounding after anything relatively small? Like walking up the hill, bending in a pilates movement. These all seem relatively small excercises. Last year I was doing weekly exercise classes without these issues but on and off I feel like this when I am exhausted. I had COVID in December and didn't feel like this during most of it. Is this Fatigue? Ive booked in to see the GP to check. Otherwise could this be the start of the menopause? I have heard that you can feel exhausted and have heart palpitations. Thanks