Green smelly poos 3 month old

My LO is 3 months old and for the past 3 days thas had really smelly poos that are green and muscusy and on Friday a couple had specks of red in them. She is EBF and has had no issues before. She has pooed around 3/4 times a day past couple of days where usually it's once in the morning, once in the evening. I had a dodgy stomach a couple of days ago and wondered if it was a little bug that I could have passed on to her, I had no other symptoms though. Other than she's crying and fussy a lot. I contacted the GP and he didn't seem concerned but it's not clearing up. Ice switched from breast to expressing to make sure she is getting enough milk and she's drinking plenty and it's still green. Any ideas?