I have a 3months old baby girl she has a little runny nose and her temp has been 99.0-100.0 for 4 days now should i be worried?

Infant with fever: Is the baby feeding well and wetting her diaper as expected? Fever in the first 12 weeks of life needs to be seen now. If present, your baby needs a medical exam now. Exception. Fever starting within 24 hours of vaccines if child is 8 weeks of age or older.

3 mo old cold: This is a low grade fever and as long as she is eating and sleeping well I would continue symptomatic care. I recommend that you plan to call her pediatrician Monday just to check her out.