Can someone find out they are autistic at 13 years old?

I dont want ANYONE to be offended by this in anyway at all, but i was just wondering (not that i know much about autism but still..), im a 13 year old girl, turning 14 on november of 2008 & i have been wondering could i be autistic & not even know it? heres why i think so:
1-I barley remember or understand anything unless its shown to me in a practical or umm..visual way? even when i was younger if my mom was trying to teach me something she would have to draw steps on paper for me to get it.
2-if i hear a really loud noise like that sound that the ambulence car thing makes, I kinda start getting super annoyed & i dont go crazy over it but only because i can control it a bit but i get very nervouse like i scream if i talk & get angry...
3-if someone annoyes me i sorta start getting kind of dizzy or numb or something. & uhmm..i breath weird..
4-teachers get fed up with me because no matter what they try i never understand & always get bad grades
so am i stupid, or autistic?

You are clearly not stupid - so that's THAT diagnosis out of the way! From what you have said, I wouldn't have thought this was autism, either, but as 1024 has said, you would need to consult a doctor to establish this.

You have explained your difficulties clearly and there is obviously a problem in terms of the fact that your ways of learning are not the conventional ones (which makes life difficult at school) and that you have such powerful reactions to loud noise, anxiety and anger. There's no way at all to diagnose you online, but I do think it would be great if you could see a psychologist (possibly an educational psychologist). The need to have things shown in a specificaly visual or practical way (what is called kinaesthetic, i.e. you have to use your body to get the sense of things) suggest a specific learning disability, and if someone can identify what is going on, you should be able to get the help and support you need to start doing well at school. You clearly CAN learn because even if your spelling isn't always perfect :-) you can write a sentence, punctuate, organise your ideas etc. My strong hunch is that if you had the right diagnosis leading to the right support, your intelligence could really flourish. You may also benefit from some specific help with the noise/anxiety/anger stuff. See a psychologist would be my best advice - and good luck.

http://www.cdc.gov/ncbddd/autism/

Hello,
There is such a wide range in autism!
Go get checked out, really does not sound like autism to me, one of my sons have been diagnosed as high functioning some things the doctor said to look out for,
ADHD which he is also diagnosed with, seizures which he also has, depression,bi polar, schizophrenia, OCD, there are more but I can not remember them right now.
Many symptoms are on the autism scale.
Hope this helps?

You can be diagnosed with Autism at any age. You could have either Autism or Asperger's. You should talk with your parents about this. Tell them your concern. You could even talk with your guidance counselor at school. You could ask her to be testing for a learning disability, and that will lead to more testing. Whatever you do, be prepared for lots of testing. Try to remain calm. When you feel yourself getting agitated, try some self-stimulating exercises like ringing your hands or rubbing your arm. I hope you get the help you need. This is a disease that is incurable, but it is TREATABLE. Good luck.

You don't sound autistic to me, but I'm no doctor. Only a doctor can diagnose you, and it's done with a lot of testing (IQ tests, stuff like that.) Takes a while but it's worth it, as there are SO many different variables within the autism/learning disorder/ADHD range. A doctor is the only one that can sort them out. Stay away from online "screening tests", as they are useless.