As IvanZ pointed out, the "Run" button (green "arrow" or triangle, default keyboard shortcut is "Ctrl+r") is to continue debug execution if it stops on breakpoint.
What you also have is "Start debugger" (F9), which starts the debugging execution, and also "Execute" (F8; in "Session" menu and also in main application toolbar - not in "Test Window" toolbar), which will execute the test script in "normal" mode (without debugging).