I'm kinda Scared of Tampons?

I have volleyball camp this week, and i have to wear spandex. I'm expecting my period anytime now. So, I think im going to pretty much have to use tampons. I already have tampons: tampax pearl lites, and playtex sport regular and super. I've had many unsuccessful attempts at tampons, and the only reason they've been unsuccessfull is because i've chickened out because when i would start to press the plunger it would hurt. So, im pretty much scared it will hurt and im kinda scared i dont really know where my vagina is? I know it sounds stupid but i'd appreciate help.