A little bit

I went for my first run yesterday. I don't like running at all. I think it's because I think, " if you run, it's very fast." And I can't run fast, I constantly force myself with high speed. And after such runs, I was madly tired psychologically. Not to mention physiological fatigue. Yesterday, I tried to run very slowly and a little. And I really liked it, why didn't I run like this before?