bleeding in early pregnancy


can someone shed some positive light for me please. I found out I was pregnant about 3 weeks ago, I've had a scan and because I'm very early they can see anything but there is a sack so very positive there is pregnancy there. I have another scan on the 18th Dec as I should be about 6 weeks then, but I'm panicking even though I've rang the midwives and our BEP clinic about this just want some more advice if anyone has experienced it. For the past week so from last Sunday (Not just gone the one before) I was bleeding but it was a spot and Brown, I had nothing then till Friday which again was a spot but alot redder. Went to a&e; and that's when I went for the scan as explained above. I've had nothing then till Monday and again today but again it's spotting but Brown. should I be very worried or is it normal. I panic because I have had 2 misscarrages in the past and would hate this to be my 3rd. the clinic have said it's normal and I shouldn't worry but just want more advice from anyone it has happened to and to know things are fine. thank you