According to the American Thyroid Association (2003), a TSH value above 2.5 is considered to be "at risk" and the patient should be tested for anti-TPO antibodies even if they are not going to be treated. This is because a TSH above 2.5 with positive antibodies indicates that the patient should be tested annually for thyroid dysfunction.
According to the 2003 statement, if your TSH reaches 4.0 and you have these symptoms, you can be treated. According, again, to the same statement, there is no harm in treated someone with subclinical hypothyroidism unless they are given a dose so high that it creates hyperthyroidism.
However, a consensus conference in 2002 between the ATA, AACE, and other thyroid organizations highlighted the need for more research into subclinical hypothyroidism. Before that time, the medical community was uncertain as to whether there was a benefit to treating such patients. Since that time, stronger, larger studies have indicated health and cardiovascular risks even to patients with minor increases in TSH (down to 2.5); and emerging research has also shown surprising benefits to treating these patients. With that in mind, if you have elevated cholesterol, you may be a candidate for treatment (as the research has largely centered around cardiovascular function). However, with many doctors, you would have to come into the office armed with specific studies showing that treated people with a TSH of about 2.5 is beneficial and not risky (as many doctors are simply afraid of treating such patients).
Considering your symptoms, many doctors would recommend that you wait about 6 weeks and do a morning TSH test within 2 hours of waking the week after your period. Hormonal fluctuations can have an effect, so standardizing the conditions of measurement is useful for both accurate testing and treatment.
Good luck.
Labs normal -- not likely thyroid related.