Been on dexamphtetamine for ADHD for 5 months, suddenly began getting strange symptoms?

Began taking Dexamphetamine in April, been taking 2x 5mg tablets twice a day since I first started on the medication, loss of appetite and weight loss are the only two side effects I have and sometimes dehydration if I don't drink enough water occasionally. normal therapeutic doses side effects include irregular heartbeat (usually an increased heart rate), hypertension, or hypotension , vasovagal response, and Raynaud's phenomenon (reduced blood flow to extremities), stomach pain, loss of appetite, nausea, and weight loss. Other potential side effects include dry mouth, excessive grinding of the teeth, acne, profuse sweating, blurred vision, reduced seizure threshold, and tics. My symptoms: Whole body tremors, cold fingers that are also numb or tingly, legs also feel numb from knees down, fatigue, joint pain and also an increased heart rate and high blood pressure... but the increased heart rate and high blood pressure are only apparent when these other symptoms are present... these symptoms are also triggered by me being really hungry, doing a lot of exercise or getting really really annoyed, but it doesn't happen every single time one of these happens... when the other symptoms aren't present my heart rate and blood pressure are normal. I know some of these are symptoms of an over dose so people keep saying I'm taking too much... can someone tell me if it's actually possible for my body to suddenly decide after 5 months of taking the same dose it's too much?