THINX and heavy flows

Anyone in here use THINX for their option of protection? I have a horrible heavy period that lasts 6-7 days. I'm going to the Dr. soon because I feel like it's getting worse with age due to my thyroid issues. Anyway, bleeding this much is making it hard to last through the night without walking up to a murder scene, and honestly it is starting to effect my daily life as well. Ive heard a few good things about THINX and wanted to hear more about it. I also would like to get away from tampons because I've heard they cause alot of issues with chemicals making heavy flows and cramps worse.