Hypothyroidism, with joint pain, stiff feet, tingeling fingers, bone pain memory issues dizzy spells and sometimes slurred speech. What gives?

Levels normal? If your thyroid levels are normal on brand name T4 replacement, then look to other possible causes for your symptoms.
Inflammation? Sounds like a multi systemic issue. Could be inflammation or something else. Must look for cause. Sometimes food sensitivities can be a factor. Sometimes infection such as lyme. Environmental toxicity also contributes.