For the passed week or so, it feels like air has been building up in my stomach(mostly when I lay down). Sometimes it makes my lower and sometimes upper abdomin hurt. It makes me feel like I have to throw up but I never do. And when I burp, the feeling kind of goes away and comes back a few minutes later. At times if it builds up lower in my abdomin, and it seems like I have to gas it out, I can't. Btw I've been kind of constipated for the last week or so too. It gets really bad sometimes. Sharp pains in the abdomin for a few seconds. I think its actually making my throat sore too. Can anybody tell me what it is?