Use the AND to connect conditions, not to make multiple things happen when a condition is met. That's what a BEGIN END block is for your example should work like this:
IF $ITEMSTATE2 = 1 AND $DEST = 1 THEN BEGIN
%OFFENSE := %OFFENSE + 1
%DEFENSE := %DEFENSE + 1
END
Or in Mizal's way
IF $ITEMSTATE2 = 1 THEN BEGIN
IF $DEST = 1 THEN BEGIN
%OFFENSE := %OFFENSE + 1
%DEFENSE := %DEFENSE + 1
END
END