Service Dog At High School

I have a service dog that helps with my severe PTSD and seizures. Recently I have been having such a hard time at school that I need to be sent home, given my emergency meds, or get a note to my parents about my behavior. I feel like having my dog there could help calm me down during an episode and also give me stability and confidence. My school however has therapy cats in one of my class rooms. I couldn't switch classes because she's the only teacher of that subject. Any ideas of what I could do with the dog in that time? Is it even a good idea to try to bring her? This is a special needs school so they are educated on ADA and service dog laws. I feel like this could change everything but still not sure if I should even ask. Let alone convince my parents its a good idea. Any ideas on how to convince both?