Clear Blue Vs Normal Upt Tester

Hai, last Thursday I ada check upt biasa. Dia tunjuk double line, tapi bila check. Kat hosp dia tunjuk 1 line dark another line tak dark Sgt.... Then doc said I kena recheck next week I don't understand why... Upt I kena check setiap minggu ke.... Then I check clear blue its showed pregnant 2-3.. But bila I scan tak nampak apa2 kenapa ye.. I'm so worried.... Please advice