Hijaab & Purdah

Women leaving the home in unattractive clothing

Q: I am a Muslimah who wears a long robe like abaya when I go out in public. Recently I have been thinking of wearing a shalwar qamees when I go out in public. The reason I choose to wear it is because it is easier and comfortable than the one I wear. With the abaya, I sometimes slip and fall, but the way I choose to wear the shalwar is different. I'm going to wear it in the way Islam has prescribed for us. It will be a full sleeved loose kurta upto the knee and a loose denim along with the hijab properly wrapped covering my head and chest.

Is this kind of attire allowed? Is it a sin on me for changing my dress from the abaya to a shalwar?