Gynecologist??

So I’m 15 and I’ve never been to the gynecologist and I need to go I am going to go and what should I expect to happen? I don’t want my mom to go with me bc I don’t want her to see you know. I’m going because all of sudden I have this smell it’s bad and it’s itchy like really itchy especially when I get off my period and I have this white discharge yet I’m a virgin but have had someone like finger me and master-bated so I’m scared she’s gunna think Ive had sex or something which I haven’t so idk what it could be helpppp😩