Nope Hero, you can be legally disabled without getting SSI/SSD.
From http://www.eeoc.gov/policy/docs/902cm.html :
Since the definition of the term "disability" under the ADA is tailored to the purpose of eliminating discrimination prohibited by the ADA, it may differ from the definition of "disability" in other laws drafted for other purposes. For example, the definition of a "disabled veteran" is not the same as the definition of an individual with a disability under the ADA.4 Similarly, an individual might be eligible for disability retirement but not be an individual with a disability under the ADA. Conversely, a person who meets the ADA definition of "disability" might not meet the requirements for disability retirement.
(b) Statutory Definition -- With respect to an individual, the term "disability" means
(A) a physical or mental impairment that substantially limits one or more of the major life activities of such individual;
(B) a record of such an impairment; or
(C) being regarded as having such an impairment.
42 U.S.C. § 12102(2); see also 29 C.F.R. § 1630.2(g). A person must meet the requirements of at least one of these three criteria to be an individual with a disability under the Act.
The first part of the definition covers persons who actually have physical or mental impairments that substantially limit one or more major life activities. The focus under the first part is on the individual, to determine if (s)he has a substantially limiting impairment. To fall under the first part of the definition, a person must establish three elements:
(1) that (s)he has a physical or mental impairment
(2) that substantially limits
(3) one or more major life activities.
The second and third parts of the definition cover persons who may not have an impairment that substantially limits a major life activity but who have a history of, or have been misclassified as having, such a substantially limiting impairment, or who are perceived as having such a substantially limiting impairment. The focus under the second and third parts is on the reactions of other persons to a history of an impairment or to a perceived impairment. A history or perception of an impairment that substantially limits a major life activity is a "disability." These parts of the definition reflect a recognition by Congress that stereotyped assumptions about what constitutes a disability and unfounded concerns about the limitations of individuals with disabilities form major discriminatory barriers, not only to those persons presently disabled, but also to those persons either previously disabled, misclassified as previously disabled, or mistakenly perceived to be disabled. To combat the effects of these prevalent misperceptions, the definition of an individual with a disability precludes discrimination against persons who are treated as if they have a substantially limiting impairment, even if in fact they have no such current incapacity.
Emphasis mine. I bolded the parts that go into more detail on the WHY you don't say what your diagnosis is - besides that they can't legally ask you that!
I am legally disabled although I do not receive any government $. I have a disabling conditions, I have paperwork about disability accomodations I have received in the past.
Employers (not sure about the SMALL employers like yours) have you fill out a form at hire where you sign off that you "can complete the essential functions of the job with or without reasonable accomodation."
I have to go now, but what I think you should be doing is thinking about what reasonable accomodations would help you to keep doing your job when your conditions flare up.
I've received "flexibility in attendance" (for Dr. appointments, etc.), "breaks" - meaning I can go sit down for a few minutes to get a pnaic attack under control. Use of a service animal. Etc. What do you need to keep your job?
Last resort is a medical leave of absense, of course.