I was in the same place as you a few years back. With me, I got upset pretty often but she'd still make me wear it whenever I had to go out. Eventually I just started wearing what I wanted to wear and at first she was against it but slowly began to accept the fact that what I was wearing wasn't anything "besharam" - although, I was known as the black sheep of the family for a bit. That subsided pretty quick cos my siblings followed suit and its almost forgotten now.
My advice, listen to your mum but if it gets too much like in my case, put your foot down and wear what you want. Explain to your mum why it makes you feel uncomfortable. And like the previous user mention, a kurta with jeans is a good idea. That was what I first started wearing when I was "transitioning" into western clothing. All the best.