I am student of interior design. When I was admitted, I was so happy to be in this field, but with the passage of time I lost my all interest. Now I am no more creative, but I am trying because this is my final year.
I'd suggest you check out some inspiring interior design sites and blogs to see if it revives your interest. Here are some sites.
Really go through these and see if you feel a fire in you!
Interior design is a field that requires more creativity and passion than just book learning. What made you want to work in this field in the first place? Do you know anyone who works in this field?
What would you really like to do? Give it a lot of thought and discuss that with the counselor also as they may be able to switch majors and use some of the credits you have in the Interior Design field.
My advice to you is to listen to your gut and choose another line of work. You have to go to work every day for many years. It may seem like you are wasting time and money now, but you will avoid a lot of misery.