Alright, so I tried out an Instead a couple months or so ago (while not on my period) and found it really difficult to get in and painful. I tried all of the hints I'd read on here, like running it under hot water to make the plastic more flexible, and using lube, but it still hurt and I could definitely feel it in me.
However, I tried one again today (first day of my period) and, to my relief, had no problems inserting it. I'm pretty sure it's behind my pubic bone where it's supposed to be, and I can't feel it in me. Sweet!
The problem is this: after inserting it, I suddenly felt very nauseated/dizzy, and had to lay down for a few minutes. I found this really strange... I've never felt this way before with tampons, or sex. I'm thinking maybe I hit my cervix (since that's where the cup sits), but my boyfriend hits my cervix all of the time and it hurts a little, but does not make me nauseated/dizzy.
Any ideas? Also, not sure if it's applicable, but I am on the BCP.