HOW TO STOP OVERTHINKING

This is my first pregnancy (4 weeks now), and I'm overthinking. Bcs right before I found out I was pregnant.. I went on extreme rides, ate junk food, and even took medication because I thought I had GERD. I felt guilty and overthinking it. Now I've tried clean food and implemented all the do's and avoid the dont's. I'm afraid I won't be a good mother/wife in the future. How to have positive thoughts??