when to worry about spotting/bleeding during pregnancy

Chrissy
Hey everyone! This is my first pregnancy. I'm 6 weeks 4 days according to my own calculations but can't see doc until 7/25. I have had some light spotting and some bleeding today and it is concerning to me partly because I am not sure what is normal or when to worry or call doc. I have normal period-like cramps so no pain really. I've read it is normal to spot/bleed during first trimester. Anyone have any thoughts/advice, etc?? 
Thanks!