Umbilical & supra umbilical hernia repair 21/2 weeks ago. A hard knot size of a ball point pen came up and is very painful. Normal? No fever, swelling

Should be looked at. Dear jenni, the most concerning cause for a bulge at the site of a hernia repair is a recurrent hernia. This would create a bulge at the same site that is painful and increases with straining. A smaller "knot, " such as you're describing, could be fibrous scar tissue, suture, or mesh. Severe pain 2 1/2 weeks after surgery is rare, so you should definitely have it looked at promptly.
Need re-evalution. You should be mostly healed by 2.5 weeks. A painful knot can represent either a recurrance of your hernia or more likely a seroma (collection of fluid). Your surgeon will need to evaluate and determine which it is.