In the USA, emergency services may be accessed by dialing 911 on a telephone and conveying your location to the dispatcher. If you do not have access to local crisis services or do not wish to use them, in the USA the National Suicide Prevention Lifeline may be called at 1-800-273-8255 at any time.
suicidepreventionlifeline.org offers chat service, including services for the deaf and hard of hearing.