Surprise pregnancy

I am in complete shock to find out I’m pregnant with my second baby. I have so many mixed emotions as this was not planned. My son is my absolute world. I have the strongest bond with him and I’m so nervous with another baby coming he is going to resent me. My husband is still shocked as summer is approaching we had plans to travel. Is there anyone who has felt these similar emotions? I just feel so taken by surprise idk how to even process my emotions.