Alhamdulillah baby okay, that's the main thing! Tapi I understand la, it's stressful when the numbers won't budge even though you're eating properly, a few of my mum friends went through the same during pregnancy and some after delivery, and honestly it can play with your emotions. Since you've already done the checks (xray, TB test, thyroid) and everything came back okay, maybe your body is just doing its own thing, some of us are just meant to maintain rather than gain, especially if baby is thriving. If you're still worried, worth a quick chat with your doctor again just to put your mind at ease, sebab they know your full picture better.