Dear @katherine987,
On the contrary, I think that the strongest thing that you could have done is what you’re doing above.
Please don’t EVER think that you weren’t “strong enough”!!! The easiest path would have been to avoid the problem - you chose the opposite and will be so much healthier for it. Put your health and well-being first, and the “adjustment” that you face this year will be just that, an adjustment. You can handle it.
Also, keep in mind that there is no one/correct “high school career”. It may sound like there is from reading these boards, but I’m sure that if you ask 90% of the parents here, they will agree. Recognize that you have options, and don’t get down on yourself for choosing a different path. That’s where you will meet all the interesting people anyway 
Good luck and keep looking out for yourself! You made a courageous first step and that’s the hardest part.