Aiyooo I had this too around that time, macam pulling sensation kat groin area kan? A few of my mum friends also kena the same thing, it's usually the ligaments stretching as baby grows, tapi better to check with your doc just to be safe especially since it's your first time and you'll feel more at ease! Since you don't have bleeding or extreme pain it's probably normal pregnancy stuff, but don't tahan if it's bothering you, call your gynae je, they see this all the time.