Scared to orgasm?

Hi ladies! I need some help. I just started to discover the world of masturbating. I'm a virgin so the feeling of pleasure is new to me. I discovered how to get myself right to the edge of orgasm but then I seem to get over stimulated and have to stop before going all the way, almost like I'm scared to orgasm and want to stop. This has happened multiple times and I have yet to orgasm fully. Is there a way to get over this and did this happen to any of you? Please let me know