Congratulations on your pregnancy!
I think it is perfectly reasonable to be feeling such mixed emotions, you've had a long journey to get to this point and by the sounds of it you were just beginning to accept it might not happen and then it has!
So I imagine you're feeling a bit overwhelmed.
Go easy on yourself, don't put too much pressure on having it all figured out just yet you have plenty of time to figure out if how you're feeling is just initial nerves/pregnancy hormones or something more.
I felt totally overwhelmed when I found out I was pregnant, I was so happy but then had a meltdown of self doubt and nerves about becoming a mum. Thankfully I'm sure it was just the surge in early pregnancy hormones!
We're all so used to hearing people being overjoyed when they find out they're pregnant that no one really ever talks about the initial fear and overwhelming sense of responsibility that comes with finding out you're expecting not to mention if you have health concerns or other added pressures. It's a big change!
Hopefully you're able to speak to your husband about how you're feeling, so you can try work through the things concerning you, then I'm sure it'll seem a lot less daunting, take some time for yourself x