If you are hammering you may be either expressing some violent feelings, or you may be reflecting on hard work and honor (depending on the content). Bright nails means you will nevertheless enjoy the work. Bent or dull nails will show sickness and disorder entering your life shortly. To drive nails shows you will complete a deal and ‘drive’ a hard bargain. If you injury yourself with a nail you should be careful of careless talk and sharp words. Additionally nails may have some sexual connotations. A man may be expressing some repressed anxiety about sexual potency and a woman may be expressing her unconscious abhorrence of sex.