Regular mushrooms that you eat are just regular fungi that you can buy at your local grocery store. 'Shrooms, on the other hand, is a term for 'Magic Mushrooms' that are a psychedelic drug that...
No, just because they stain a certain color doesn't mean it's safe. You need to I.D. shrooms before you eat them man, take some pics of it and post an id request on a website like shroomery.org