The school did a poor eval (at my request--they didn't want to actually evaluate her). All they cared about was whether she did or did not score below average for writing on a test like the Woodcock Johnson. They told me that any other testing is "neuropsych testing" and they do not need to do any of that. However the State manual for assessing disabilities like SLD states all of the appropriate/suggested tests and there is more there than the Woodcock Johnson! They are supposed to assess for information processing disorders. She qualified as having an SLD due to severe discrepancy between cognitive ability and achievement but they told me she has to be below average. I rejected the school eval and put in a request for an independent eval at public expense. School districts almost always grant this request (although they may hate you) otherwise they have to go to due process which is expensive for them. It is the most powerful right a parent has. You do not need to accept their eval. They sent me a list of evaluators but a disability lawyer told me they were all unacceptable people and gave me other names, so I had DD evaluated at a University by a neuropsych/ed psych (I think the educational psych part is important--that was more important to me than having a neuropsych, because I wanted recommendations for the school and something the school could relate to). Once we get around to having another IEP meeting he is going to attend.
My DD seems similar but she doesn't really freak out in an obvious way. The only reason they know she is anxious (now) is because she started telling them. Sometimes she starts crying. Most of the time, if she is overwhelmed, she just sits there and does nothing. On a test to place her for math, it was multiple choice and she picked random answers to get it over with.