Seeing happy pregnant women makes me sad

Hi everyone. I’m not sure what I’m looking for through this post, maybe some support or advice. I’m 18 years old and I got pregnant on the pill, I found out I was pregnant when I was 6 weeks and made the very tough decision of getting an abortion a little after 7 weeks. Although the decision was the best for me and my boyfriend, I really regret it. Abortion has always made me uncomfortable but I knew though it was hard, it was what had to be done. I struggled mentally for a couple weeks after and now here and there, but now every time I see a happy pregnant women flourishing and doing great it makes me sad. Of course I’m happy for them, but it makes me feel like I’m a horrible person and that I wish I could go back in time and change my mind. Someone please talk to me or help.