Why am I having bad dreams of my newborn being hurt?

Three months ago I had a little boy and the first month he was born he was in and out of the hospital with Jaundice, RSV, pneumonia, bronchitis, a blood transfusion, and breathing problems. Ever since he was released I have very vulgar and descriptive dreams of people hurting both him and I, for some reason I always end up dying saving his life or something beyond terrible happens to him. I have these dreams almost every night. He's completely healthy and so happy and I would NEVER let anyone around him that I don't trust. The dreams get me so scared I hardly ever leave the house and I canceled my plane trip to Texas because I kept thinking the plane would crash or a terrorist would bomb the plane. I don't know if this is just because I am a new mom and I am paranoid something bad will happen to him, or do you think I should talk to a counselor? I've never done drugs, I don't drink, and I've never had mental problems in my life. So why all of a sudden am I so paranoid?