Threw up a lot, stomach still churning a week later. Feels tight and heavy, not gas. Dark colored stool. Got very sick about a week ago, throwing up every half hour for 10 hours (literally 20 times of heaving and throwing up bile in one day) - I thought it

Not sure what you. Mean by dark colored stool. If you have black, malodorous, tarry stool or you vomit material that looks like dark coffee grounds, either of those could be signs of GI bleeding. This would merit medical evaluation.
Yes . Yes it probably is a bug. But if it doesn't go away you need to be seen by a health professional.