2.5 weeks lazy at breast


the last two days my daughter has been only wanting to nurse one breast and then is too sleepy for the second. today she has been lazy about both breast, she seems to be more sucking for comfort than to eat... but it's been like this all day! I also noticed the last two days that my breasts always feel soft, no fullness at all. I'm just worried she is not getting enough milk and is maybe becoming dehydrated (my son got dehydrated while waiting for my milk to come in and was hospitalized so I have constant flash backs to that) she has had good wet and dirty diapers (pooping almost every time I change her which also concerns me because me and my son have had diarrhea) please give me advice and hopefully some positivity before I rush both my kids to the Dr first thing tomorrow morning.