Should I tell my one night stand im pregnant?

I recently had a one night stand. I just found out I'm pregnant. A baby fits nowhere in my five year plan. I do however intend on keeping it. I'm not sure if I want to or should tell the father. He's 27 and i'm 19. I assume he is mature enough to take responsibility. I am however uncertain how and If am going to tell him.
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+1 y
I am planning on telling him. I guess my question was really how should I tell him?
Should I tell my one night stand im pregnant?
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