blood in baby’s poop

i’m so worried this morning there was a few specs of blood in my babies poop (she’s breast fed) and it has progressively gotten more as the day goes on, but not a large amount. it seems like she’s straining to poop when she poops and when i called her doctor he said it sounds like an anal fissure and to call tomorrow if it gets worse. i’m just so worried about her ive been crying all day😭😭 she’s only 3 weeks old