USA Tax refund, 3 months internship in another state

[April28]

Hello,

I have couple of questions regarding the tax refund in US.
I am a graduate student in an university in Indiana, so I got paid in Indiana.
And I am doing an internship in Iowa last summer.

My questions are:
1. How many forms I have to files?
I assumed that I have to file two (one state and one federal tax refund for Indiana)

2. How about the one in Iowa? Do I have to file both forms too? Are the forms different between states?

Your answer and direction will be very helpful.

Best,
April