Underage pregnancy ... (No hate, Please)

I recently have take 4 home pregnancy tests... All positives... I dont want to tell my mom just yet .. An i dont want her to find out i made a doctors appointment for an ultra sounds .. I want to tell her my self ... But the thing is i dont know where to get an ultra sound that wont send her any billing information or an email or anything ! Its must that she finds out by me !

And i dont want her to think im playing with her.. So i want an ultra sound picture to be able to hand to her... Any suggestions where i could go, that she wouldnt find out by billing or email or anything?....