First time use

So, here's my story.  I am 30 and have had two kids, one vaginally and one C-section.  I just heard about "Diva cups."  Not realizing there were several different brands, I saw a deal for the Dive Cup and bought one.  I got it the day my period started.  So, I tried it.  I am not having a problem getting it in.  I am using a 7-fold.  The problem is that I think that it is too long for me.  I didn't measure before I bought or tried, didn't realize that I would need to.  I can feel that my cervix is actually sitting inside the cup.  I can feel the cup all the way around my cervix and it isn't leaking.  But, the cup isn't all the way inside of me.  I trimmed off the entire stem and turned the cup inside out, but it still protrudes just slightly from my body.  Do I need a shorter cup?  I was thinking on trying the Size A (large) Mooncup UK, since it measures the shortest.  Any suggestions on where to get it, how much or any savings codes would be appreciated.  Thanks so much for any insight.