Firstly as others have said baby is mostly definitely healthy.
My stepson (who I have brought up as my own since he was 6months old) is a perfectly happy, healthy, intelligent 8 year old after a less than perfect pregnancy. His biological mother (my husband/his dad did not know she was pregnant) drank a lot, took drugs and did not care for herself at all throughout the pregnancy with him. And as I say, he is more than fine.
I also know a teenage girl who only found out she was pregnant 2 weeks before she gave birth and her now 18month baby shows no sign of problems at all.
As for you mental health, it can be very scary making the descion to have a child and when it happens quickly I can imagin it can feel out of your control and not prepared.
We had always talked about it. I had done the parenting bit, but not the pregnancy bit. I realised I was terrified about even thinking about trying to conceive. Terrified about all sorts of things, how would I cope, would I be a good mum, would I love my baby, suffer PND, would my husband still love and fancy me, would I become isolated, the list went on.
No one could really soothe my fears, but eventually I found piece with them in the stillness of calm thought. They no longer worry me. The talking did help, even if not a lot at the time.
I really hope you find piece with yourself and your actions. You have not already been a bad mum, you care enough to consider all options. You are human, try not to chastise yourself for being one. You already love your baby to want the best for them. Hold on to that love.
Get the help you need xx