Sims needs are going down too fast.

My sims needs are going down super fast. My sim is in University (idk if that is why) but I send her to sleep and then she is bursting for the toilet, she goes and does her business. Like 2 hours after that (sims time) she is bursting again and I mean red bar! Same goes for hunger and hygiene. My other sims can last nearly 2 days without showering and they are fine, but this sim needs like 2-3 showers a day to keep it in green..??? Does anyone know whats going on here? Thanks.