Well, I ordered an extra-small MeLuna before going home on winter break, and when I came back today, I was on the fifth day of my period. So I thought I'd try out the cup once I got my books, etc. from the commons. With great trepidation (and some lube), I shut myself in the bathroom and gave it a try.
AND IT WENT IN!
At first, there was that same stinging, stretching pain that I always feel when I try a cup, but I tried to follow the natural curve of my vagina. The cup kind of curved, then popped itself into place.
Question is, how do I know if it opened adequately? When I took it out, I could feel a good strong suction holding it in place, and once I got past my vaginal opening, I couldn't feel the cup inside me. Is that an indicator of a cup opening?