Yes you can, remember that where you insert the tampon is a completely different hole from where your wee comes out of. Oh, and when you're weeing, the tampon string might get a bit wet so you might want to hold it out of the way whilst doing so :)
Did it go down the toilet? It was probably just a clot, though you may have had a very early miscarriage. It is thought that about 50% of pregnancies end this way.
Yes, of course you can lay down when you are wearing a tampon - just don't sleep with tampons in. There's no reason to think that you wouldn't be able to lay, sit, or stand-up wearing a tampon. If you have problems laying down while using a tampon then you may not have inserted correctly.
Yes, you can go into the ocean to surf when wearing a tampon. You can also use options like menstrual cups or softcups which are more convenient and more reliable than tampons.
Wearing tampon may block the flow sometime. That too if you have irregular periods better go with a normal one. In case of emergency requriements you can use tampons
Of course it would be 'gross' to change your tampon in class, just as it would be 'gross' to go to the bathroom while you're in class. If you need to change your tampon simply let your teacher know you're going to the bathroom and go change as anyone else would. Ideally time changing your tampons so you can do it between class rather than missing your lessons.
I'm not sure why you would worry that this is not safe.Tampons generally aren't safe but as long as she is following precautions her risks are reduced, going in a hot tub while wearing a tampon isn't going to increase tampon risks. Girls go in hot tubs all the time without a problem, there's no reason to think that this would be a problem either.
Yes, you can still urinate while you're wearing tampons. Tampons go into your vagina, and you urinate from your urethra - they are two completely different holes. If you're using tampons with a string it's a good idea to move the tampon string out of the way so that it doesn't get wet, as it can be unhygienic and uncomfortable to walk around with a wet tampon string. It's a good idea to try to time changing your tampon with urination, just so you don't spend all your time in the bathroom.
Nothing will happen, it's just like wearing a tampon at any other time. It is possible for water to be absorbed by the tampon, meaning it can leak or feel a little uncomfortable, so make sure to time it to insert just before you go swimming and check after half an hour to an hour.
No, you shouldn't feel like you need to urinate while wearing tampons. Tampons go far enough in the vagina so that there shouldn't be pressure on your urethra or bladder. Chances are if you feel like you need to urinate a lot it's because you're drinking more or maybe have a urinary tract infection.
There is no way that you would be expected to sit on a boat for 15 hours without any access to a toilet - it just wouldn't happen, if you have access to a toilet then you can change your tampon and pads. If you are ever in a situation where you can't change a tampon every 4-6 hours then you shouldn't use a tampon, you can leave menstrual cups or softcups in for up to 12 hours so could potentially go a little longer without risk.
When you need to change in school just squat down like you do at home, ideally try to do this when no one is in the stalls near you. Alternatively practice inserting tampons while sitting down on the toilet with your legs apart. Another option would be to put in a tampon in the morning then change to pads at school when it's time to change your tampon - best to alternate with pads anyway.
The gravitational pull manages to bring the poo from your bum hole directly into the toilet ( white or black toilet , or prefered colours+ fur) unless, you really have the urge to go and you are not next to a facility, then they are possibilities that you may go in your underwear, if you are wearing any.. if not, then it will go in to your pants, if not wearing pants , then it will go into the gravitational pull and start orbiting the sun. When it enters our atmosphere , someone will get a concusion of flying, random piece of YOUR poo!