Anti-anxiety medications can make you drowsy. If all other symptoms are taken care of, then a dose adjustment or adjustment of timing of medication may help. However, if your symptoms are still persisting, then you need to get investigated to find the cause.
Extreme fatigue could be due to menopause/hormonal imbalance of PCOD/low testosterone in males, anemia, diabetes, hypothyroidism, or due to kidney or liver problems. Another possibility is sleep disturbances (like sleep apnea, imbalance of rapid eye and non rapid eye movement sleep etc.). You may sleep your customary 7-8 hours and yet feel fatigued. You need sleep studies to rule this out. Other possibilities are chronic fatigue syndrome, depression, low Vit B12, low iron, low calcium, sodium and potassium. Hyperthyroidism too causes increased sweating and tiredness. Postviral fatigue syndrome is another possibility. Persisting EBV infection or mono can also be the cause. A comprehensive investigation is required keeping all the points in mind. Do discuss this with your doctor and get yourself examined. Take care!