I've been having this brief but really intense pain right in the middle of my chest, and it only lasts for a second. It kind of feels like something's bursting in there, and it happens when I'm just resting. It's pretty scary and I'm not sure what I should do. Any thoughts?

It sounds like you may be experiencing a condition known as angina, which is chest pain or discomfort caused by reduced blood flow to your heart muscle. It is important to seek medical attention immediately to rule out any serious underlying heart conditions. I recommend taking a low dose of aspirin (75-150mg) immediately, as it can help reduce the risk of heart attack. Additionally, you should take a sublingual nitroglycerin tablet to help relieve the chest pain. It is important to rest and avoid any strenuous activity until you can see a healthcare professional for further evaluation and treatment.