It's OK to feel sexually aroused while dressed. For me, once I was introduced to the feel and look of lingerie at the age of about 5, dressing up became an integral part of my sexual exploration and development. It is still there but now there is another component that has more to do with how I feel about myself and the joy and comfort of presenting as a female. I enjoy beautiful feminine clothing and lovely jewelry etc.
Please, never fell guilty about this aspect. It is normal and natural and we don't need to take on a guilt that is imposed by society and especially by religion. Sexual arousal is a completely normal thing for humans and all animals. How it is triggered does't matter.
