Telling mom about pregnancy?

I'm 20 years old pregnant with my first child.. I just took a home test & it came back positive.. actually i took 2 and they both came back positive. I'm a little worried about telling my mom about it even though I'm sure she's not going to kill me or anything! I'm a little uncertain how her reaction will be even though before I became pregnant she's always been saying things like how the line on my belly will look once I'm pregnant & when she watches her friend's baby she makes like it's her granddaughter sometimes & she even had a dream about me being pregnant she came to me about it asking if I was on birth control cause she had a dream but with a grin on her face! she didn't have a serious look at all!! she's told me before how proud she was that I didn't conceive as a teen like she and my grandmother did at 17. I'm not too sure how I should approach and tell her. I'm thinking of whenever I have my pregnancy confirmed and I have proof of pregnancy I will come to her in person and show it to her. I'm definetly not wanting to call or text or e-mail.. that is ridiculous but I would like to know how I should get myself confidence to tell her I don't think she will do anythin or say anythin horrible but there's always that chance hearing news like this!