I (24M) broke up with my gf (25F) after a month, did I make a bad decision?

To give some background, I was in a 5 year relationship that fell apart because my own infidelity and failure to be honest. After a couple months of recovering from a world shattering break up, I found someone who made me feel hopeful again for a relationship. We spent a couple months growing closer and enjoying each other’s company. I had asked hee to be my girlfriend last month and things were good. As time progressed, I caught myself feeling different in some ways and becoming less attracted to her. We would get along so well and clicked well, we had similar viewpoints on life, our sex drives matched well, she treated me well and I tried to do the same. I just kept finding myself thinking there’s more than this out there. I would think about my ex sometimes and think about other women other times. I felt wrong for these feelings, and they wouldn’t subside, so I pulled the trigger and broke up with her this morning before we we’re supposed to go run errands. It devastated her, but I fear that if it wasn’t now, it could’ve been worse if I dragged it out or lied to spare her feelings.