Help! Holding in sadness?

I'm the type of person who holds in my sadness, tiredness, and anger. I put on a happy face in order to make the people around me happy, but deep inside I feel like exploding. However, now when I need to cry, I can't and when I need to be angry, I can't help but add a smile at the end or laughing it off. Sometimes I sleep 1-2 hours everyday, but I continue to act hyper and excited for everything when deep inside I am extremely tired. Now, I can pull an all nighter without beng tired. I may be tired momentarily but I push it away. What should I do? I can no longer feel angry, sad, or tired, but I always feel a throbbing feeling in my chest. It feels like I'm about to cry but I can't. Please help!