How to tell my mom I’m pregnant !!! 🤯🤯🤯🤢

Hello! I am 18, a senior in high school. (How exciting) lol anyway, I am four months pregnant, and don’t know how to tell my mom! I get really anxious and nervous just the thought of it. My mom had me at 16 so she was super young. I saw a lot of the struggles and tough times she had to go through. I feel disappointed at myself, and I’m sure she will be furious... I just want a good way to tell her. I obviously don’t wanna mention how far a long I am because i dont wanna make her feel left out, or that I hid it from her. But I know I have to tell her, but i freeze! But it’s time to tell her & if anyone knows how I could make it easier upon the both of us ?