How do I tell him?

I was sent home from work on Thursday for throwing up (standard protocol for them) and could not be cleared to come back until I got a negative Covid test result. Went today and the NP did a whole work up and said I should take a pregnancy test which came back positive.

This was very unplanned and we are not in the most stable of places financially right now but my initial instinct is to keep the baby. I haven't told my partner yet and I'm unsure how to tell him as we've been particularly careful the last month and a half and I'm fearful of his reaction. Any advice?