I'm really worried about my wife. She's been on TB treatment for a month now, but her cough hasn't really gotten any better. Her appetite seems fine, and she's even gained a few kilos. There's no fever or sweating, which is good, but the bloody cough and irritation are alarming and she's feeling really fatigued. Her chest X-ray shows sputum negative. What could be going on, and what should we do next?