OFF THE SUBJECT: MY 3 YR OLD IS OBSESSED WITH CLOTHING! HELP!

I don't know what has gotten into my daughter...she is obsessed with clothes and it's just not clothes, her obsession is with SHORT SLEEVES! For the past few months, a day doesn't go by without the same conversation about how she wants to wear short sleeves...she absolutely REFUSES to wear long sleeves..she also wants to change her clothes like 6-10 times a day..she will go as far as put something on her shirt to make it look dirty so I will allow her to change it..

I have no idea what to do..should I allow her to be able to change that many times a day? a friend suggested that I put a time frame on the next time she can change..for ex. tell her that at 2:00 she can change into a different outfit but not until then..

I am very pleased that she is potty trained finally! She will be 3 in May so we accomplished it before her 3rd birthday but I have been told by family members and friends that I am not strict enough with her..I have been told that I should be making her wear what I want her to wear..not letting her choose..my therapist tells me that even at her age, she should be allowed to choose what she wants to put on..
I'd love to hear some of you guys' suggestions on this topic?