when in a shower, either don't be shy or use the smallest swimsuit your comfortable in and turn away from the others to have some privacy during the cleaning of the unspeakable parts, but I believe if the trip is under 5 days, you shouldn't have a problem with showering/bathing as long as you don't get completely dirty like fall in a mud pit, but any longer, it's recommended, try shallow river pools up to your waistline, any deeper and your risking undertoe and shallower is a inconvenience.
sleeping? depends on the conditions in the area, bring a lot of layers while camping, so you can remove and add layers if your too hot or cold, same as on the trail.
this all goes for boys and girls