I switched to a cup this year and loved it... for the first couple cycles. I'd noticed a few times feeling like it was sort of.. slipping down? It was still in there so I thought it must be in my head, but I would change it just in case and go back about my day. Until one day it fell out. Fortunately I was at home! I'd started being able to feel the cup down there near the end of my work day, as I had sometimes before. I figured I'd change it when I got home. I continued feeling uncomfortable through my drive home, and when I got there, my husband was in our only bathroom. But then, while I was waiting in the kitchen it happened. I suddenly realized it was not just in my head, the seal broke, the cup slipped out far enough into my panties, and Niagara Falls poured out all over my pants. Now I'm terrified to use it again! What if that had happened at work? Long story short, experienced users, what do you think could be causing this? The cup had definitely been in properly all day prior to this, with no leakage. Could it be too long for me? Does being too firm or too soft cause this? Why does it keep slipping out?! I don't want to be too paranoid to use it again! Help!