I've been inpatient 7 times between 3 hospitals, so I can give you a general run down.
weekdays:
-waken up for vitals around 7am, some places they'll come to you, others you come to them in the community room
- goal setting
- breakfast around 8-8:30
- first group around 10:30. could be talk therapy, recreation, etc.
- lunch at noonish
- second group around 2
- dinner around 5
- visiting in the evenings on certain days
- lights out at 11

weekends are a lot less structured, there aren't usually groups.

Plan on a lot of downtime. If you can tolerate reading or coloring bring those things with you.

Out of all 7 stays I've only had one crappy one, so it can happen but I wouldn't say it's the norm.

When you check yourself in, you'll go to an ER and tell them about your feelings. You'll give blood and urine samples so they can see if there's anything physical causing your symptoms and if you're on any drugs or pregnant. Once those results come back, they'll call in the social worker, who will talk to you in depth about your feelings and your plans to hurt yourself. They will decide if you're enough of a risk to go inpatient. Since you're a teen you won't be checking yourself in, your parents will be doing all the paperwork on your behalf, but you're still considered voluntary which is a good thing. You'll be transported to the psych unit, where they'll strip search you and make notes of any marks on your body, then someone will go through a million intake questions with you while someone else checks in all your stuff and inventories it. No belts, shoelaces, drawstrings, jewelry, metal hair accessories like bobby pins, electronics, cell phones. Bring comfy clothes, like exercise/yoga pants and tshirts and a non-hoodie sweater, enough for about 4 days (they have laundry on unit).

If you are still feeling suicidal once you get there and you don't contract for safety or you get someone that you've contracted with then they'll assign one person to be with you around the clock until you start feeling better.

Generally yes, you do get meds. You can refuse if you want, I didn't want to go on meds my first hospitalization but they basically told me you want out of here you have to take them, so I did for a while and then went off with my outside doctor later.