I've been feeling more tired and have some dysuria. When should I see the doctor?

Fatigue & dysuria. These are generally two separate problems. Dysuria may represent a bladder infection, so you should have your urine checked. Fatigue is a common nonspecific symptom associated with stress, illness, depression, or chronic disease. Most people can cope with short-lived, episodic periods of fatigue. If it lasts longer than 2 months, however, you should consult with a doctor.
Now is good. A bladder infection (cystitis) is easily treated and should be; to avoid worsening infection and/or scarring. Feeling tired (fatigue) can be caused by many factors. Your physician can assess your risks for anemia, thyroid disorders, depression, stress-related symptoms among many other medical problems that can be screened for by your primary care physician. Please go get treated & evaluated.