Congratulations on the birth of your son. I can imagine how elated you are after having such a difficult time conceiving. And so it does make sense, on some level, that you would be having some of the thoughts you're experiencing, because you've had such a rough time in the past. I'm thinking that part of what you might be experiencing could be post-partum depression. It's not uncommon - and it can cause some of the thoughts and feelings you've described. Feeling like you'll be a bad mother (which you most likely won't be), feeling that something may happen to him (which it most likely won't) are very common symptoms - and you're having some anxiety
mixed in with these feelings of depression, which is also a part of post-partum depression. I'd like to share this information from the Mayo Clinic with you, so you can review the symptoms and see if you feel it fits with what you're experiencing now:
Now, part of dealing with these symptoms requires medical intervention - so talking to your doctor about the way you're feeling - he or she may suggest anti-depressants, which are proven to help these symptoms. You might also think about seeing a counselor, because you can talk about your feelings and concerns, and the counselor might be able to help you develop better coping mechanisms and help you to see things in a more realistic light. You can also learn how to deal with the anxious feelings that are a bit more severe - such as not being able to breathe. In these cases, you might find it helpful to practice diaphragmatic breathing - (or abdominal breathing) - as it can help you calm down, feel more relaxed and ease some of the anxiety. You can read more about that here:
I'd also like to share with you some more information about the treatment options for post-partum depression in case you'd like to look into it further:
I hope this helps. You're not a bad mother, and you're not doing anything wrong - you just are most likely dealing with some hormonal changes that can be treated. And these feelings won't last forever.
Please let me know if you have any more questions. Best of luck.