Don't worry about her not liking it. She has to go anyway. It's a long day for her - I've seen kindergartners fall asleep on the bus, and the bus driver have to pick them up and hand them to the mom - out like a light!!
I hope you can get some help with the allergies - you're right - they wear a person out, child or not! Kindergarten is a lot of work, unlike preschool.
Is your child young for her class? If she is, that could be part of it. If not, just give it time. Hopefully they don't have her doing homework.
As a heads up for the upcoming summer, if she still struggles with fatigue and hasn't "warmed up" to school by the end of this school year, consider getting her a tutor to teach her to read, IF she isn't reading primers fluently by the end of this school year. I wouldn't normally say this, but if she struggles with fatigue, first grade will be really hard, and there is homework in first grade. There's also a lot of stress in reading and writing. If you can make it so she hits the ground running in reading and writing by the time she gets to first grade, using an easier summer schedule, it will really help her.
Handwriting Without Tears by Jan Olsen is a wonderful program to use. My younger son had issues with a weakness in his writing hand, and I took him to an OT who offered a group class using the program. It was great - he learned to write and strengthened his hand at the same time. I did it before kindergarten and all through kindergarten, and part of first grade.
Good luck,
Dawn