Very likely diabetes. You need to be checked for diabetes. Especially if you are having symptoms of diabetes out of control, such as, excessive urination, thirst, and/or hunger. If you have diabetes it is not controlled. Either way you need to see a doctor and soon.
High blood sugar. Blood sugars can be tested by using a "fingerstick" prick and a device that checks the concentration of sugar in the blood. Normally well below 200, thus 423 is very high and indicates poorly controlled diabetes and 241 is mildly elevated.