The look on Taj's face was the pain of being more revealed than he ever was before. He thought this was proof in the puddin' of his feelings for Andy and they would be interpreted as such. Andy never could interpret these types of things quite right. From Taj's view he just got caught in the middle of an act that would confess all that he still wanted to be with Andy. And by "be with" that didn't mean sex. That meant the real deal -commitment- the happy ending that was never resolved from their childhood. And the pain in his face was the fact he knew Andy wasn't going to give it to him. The tuck-in cuddle-up was what it always was. The fact Taj always turned to Andy for all his pain, even if that pain was in fact Andy. That's just how oddly comfortable he was with him.
But for as much as Taj understood his brother, he really didn't realize that Andy's offer was quite coming from the place it was. He didn't realize that Andy wasn't seeing this 'being caught' moment in the same light that Taj was feeling it. He lifted his head to meet his eyes. Did he really just say that? Taj's eyes bore some mix of confusion and hope and fear. Confusion that he may have heard him wrong. Hope that maybe he did assuming it meant what Taj thought helping would mean. Fear that this could change everything. He knew Kareem was against this. Kareem was really against this. "Help how?" Taj had to get clarification thinking Andy was admitting back what Taj was feeling all along. After all this time gone by it was hard for Taj to believe what was sitting before his eyes.