I'm going to take too long in the shower
Are you really considering this? How much longer will you be taking your showers?
I will take at least 5 more minutes, may be 10.
You shouldn't take too long in the shower in general. Someone else may be waiting to use the shower and it's unhealthy to stay in the shower for too long.
I don't really care, I'll take as long as I want.
You never know for sure if someone is in a hurry and needs to shower too. How about telling people beforehand that you want to relax a little longer?