Sanitary napkins and tampons don't leave bits of cotton behind. Both products are sterile. Both products are designed to absorb blood. Both products have the same medical characteristics as surgical sponges and compresses. What your lady friends know as a tampon was invented to ... wait for it ... stabilize battlefield bullet wounds. Today we have the Celox applicator to apply a clotting agent directly ... wait for it ... into the wound.
Ferpitysake, chill. Yes, bullets do awful things to a body. Yes, the wound channel is unpredictable and messy. Start where you stand. Stop the bleeding. Maybe you can't stop it all. Less bleeding is better than more bleeding. Keep the patient alive long enough for the ER to deal with the internal situation. Blue bold underlined text doesn't make the content congruent with reality. Jonathan D's source is deadly wrong in all respects.
Here's a crazy idea: Wot eff my FAK has ... wait for it ... different sizes of gauze? What a concept! No, I don't go into the woods with only a Kotex. I do go into the woods with itty-bitty Band-Aids ("plasters", yes?), my most-used 3/4" cloth Band-Aids, knuckles, fingertips, 2" gauze (used one last weekend when a wood chip split my thumb knuckle and it bled like a pig.), 4" gauze, 4" sponges, and yes, yes, my misogynist friends, a Kotex. I think there might be an ABD pad in there somewhere, but I'm not opening up all the zip-locs for voyeurs. That's just the backpack kit [compress section]. I have a trauma bag in the back seat. What? Yes, crikey, I have the training.
Besides, some day you'll make a companion hiker very grateful when you say, "Yes, I do have a spare pad. You're welcome." Bonus points if you're a guy.
Axes make nasty wounds, too, and do so more frequently to perusers of this site than do bullets. All of the above applies.
Future readers of this sticky thread: Get trained. Then read some useful books. The training is constrained by lawyers and the medical industry. Nevertheless, get trained. There's a lot of "do no harm" daylight between training courses and what you can do for yourself or your fellow hiker in extremis.