The white tissue is probably nothing to worry about. And the hole doesn't have to be round. As long as your only symptoms are soreness or tenderness, you are probably okay. Continue warm salt water rinses, they are the best for reducing swelling and soreness. If you start having severe pain or throbbing, then you should see your dentist. Don't try to get that white tissue out, it needs to stay. It is like scar tissue, will go away and you'll be okay.