This is one of those things that you just have to figure out as you go. I can understand his being hurt that you kept this from him for a little while, but I think his reaction is commendable, and you can repair that rocky start by being wholly honest and truthful from now on.

Communicate, communicate, communicate. The best chance your relationship with him has is if you talk, and talk, and talk.

No more secrets from you, missy.

I also highly recommend you should go see an obstetrician (most GYNs also do this); talking with them about your concerns with your pregnancy will certainly help.