I'm having a hard time breathing and feel like I need to open my mouth every now and then just to catch a breath. It's weird because my breathing seems normal when I'm sleeping, but it's like something's blocking my throat. I don't have a fever or body aches, but my chest feels heavy and I've got this gassy feeling too. I tried holding my breath for 30 seconds and it was fine, but I still need to take deep breaths through my mouth, and even then, it doesn't feel quite right. What could be going on?