Is it normal to have severe cramping and light brown spotting, positive pregnancy test, best guess, 4 1/2 weeks pregnant?

Needs evaluation : Bleeding in early pregnancy may be common but it is not normal. You need to be seen urgently to verify the pregnancy and to verify that the pregnancy is located inside the uterus. An ectopic (tubal) pregnancy can present with pain and bleeding. This is a life threatening situation. Even though an ectopic pregnancy is less likely than a normal pregnancy prompt evaluation is warranted.