Perhaps you need to be checked out but in my experience my period flow had changed over the years. So yours could too. Get checked to be on the safe side. Talk with your mom.
Try Kotex super plus as they are the best I tried for heavy flow. Then use a pad also. At least you can get really thin pads now.
You need to get checked out by the gynecologist and get tested for anemia. It takes a while to get iron levels back up and it will steal all your energy if you are anemic, so taking iron early instead of waiting will help you.
This is the one situation where I'm not against birth control pills, because it's really hard to be in school, where they have you on such a tight schedule you have no time to change in the bathroom. So discuss it with the gynecologist, emphasizing you would want to try the kind that lessens flow. Be aware you will be more susceptible to yeast infections and it can cause other issues like mood problems. Try taking magnesium and vitamin D in the morning and calcium at night to help you feel better, whether you start the pill or not.
Using 2 tampons at once heightens your risk for Toxic Shock Syndrome, which can be fatal. Switch to pads when your flow is that heavy. Use overnight ones. And I know it's worrisome that someone may see your pad through your pants. I am 43 years old, and used to worry the same at your age. It's simply untrue. I have worn virtual mattresses (they used to make very thick pads when I was young) with my tightest jeans, and they just don't show. Your next step is to get with your mom about seeing a doctor about it, as there may be something to be done to control it, like birth control. Blessings - Blu