I have weakness and pain in my left arm is this bad? also all day having chest pain in the the top middle of my chest

Get it checked out: Chest and left arm pain should always be taken seriously. Given your young age coronary issues are unlikely, but other things (like pericarditis, myocarditis, hypertension) need to be ruled out. It could be musculoskeletal (likely if related to certain movements or reproducible). Pulmonary or pleuritic causes should be considered (especially if short of breat or pain on inspiration). Gerd also.