Alternatives to tampons

I’m sick of spending so much money on tampons and also of putting unknown chemicals in my body. I have looked at “organic” and “natural” tampons, menstrual cups and sea sponges. My question is which one to go with? I have a very heavy flow, talking super plus here, and I get insane cramps. Pads give me the heebie-jeebies, so I need a tampon alternative. I really like the idea of a menstrual cup or a sea sponge. But what I’m wondering is, as lame as it sounds, how do they work? Insertion like a normal tampon? Can you feel them? Can you have sex with a cup or no? Etc. Any info would be amazing! 💘