First period with copper IUD

Omg, it started 4 days ago... well the cramps started 7 days ago... no too bad, I drank 2 advils every day and I didn't feel much, when I did they hurt but they were mostly subtle. The first day of my period was very light, almost like spotting and the second and third day were normal.. today though, I changed my 'super' tampon twice in one hour b/c I leaked TWICE. In one HOUR.it was a bit ridiculous so I bought ULTRA sized tampons, let's see how this goes. Usually I only had to change my super once every 3-4 hrs.

Does anyone use a menstraul cup? I'm a swim instructor and I'm in the water all the time so I'm really scared of leaking. Any tips?