You may have a hard time making friends. You may have difficulty figuring out how other people feel and why they act a certain way. You may like to talk about topics that other people do not seem to find interesting. You may feel more comfortable when things always stay the same. Colds and measles are diseases.
Autism is different.
Autism is a developmental disability and its effects will always be with you. People with autism live a normal life span. Hopefully, you will live to be 70 years old or more. No one knows exactly why your brain developed slightly differently. The differences probably occurred while your mom was still pregnant with you, that is, before you were born.