Lemonpawz, The feelings of embarrassment are very, very, very normal...whether you are 15 or 51. As Petals suggested, please let your Mom know what's going on. I can assure you that the doctor wants to know information such as this and will not be "grossed out"....of course, neither your Mom. Start at a young age talking to your doctor about symptoms...they went to school for many, many years and are very knowledgeable but they are not mind readers. I say this with first-hand knowledge because I am one who went to the doctor for many, many years expecting him to read my mind rather than squaring with him on symptoms!
I am 52 and just recently told my husband and my doctor about my bleeding. I know exactly what you are talking about but I can assure you it was soooo much better when I got it "off my chest"!!
Take care kiddo and I'm so proud of you to post your question the way you did because I really think you will help a lot of people (young and older) realize exactly what they fear the most...embarrassment. Got a good feeling that you are gonna be just fine...keep us posted!