Your first egg has what is called a "blood ring"....that's where the embryo had started to develop, but for some unknown reason---it died. Second egg...can't really tell anything.
I candle on day 7, day 14, and then day 18 before they go into lockdown. I don't believe it harms the eggs; I candle them as they sit in the turner. Actually, I believe the few minutes of change in temp & humidity, while I candle them, may actually be good for them----think about how the hen gets off the nest for a few minutes each day....