Eating Schedule

I agree, if she's still congested that might be the issue. It's also possible she needs a higher flow nipple.

It's a little early for cereal. Cereal has little to no nutritional value, so she still needs formula and breastmilk - by filling her up on cereal she'll just want less formula/breastmilk. Introducing cereal too young can cause an increased risk of choking, especially when it's in a bottle, plus their little digestive systems aren't ready yet.

Our daughters are about the same age, mine was sleeping through the night here and there, now she's also back to waking 3 times a night. I figure it's a growth spurt and/or teething. Most babies don't sleep dependably through the night until they are at least 6 months old - and even then they still wake up from time to time.

Also - if it's teething, no Motrin yet. Just Tylenol.

Don't do the cereal. She probably just got used to this schedule so that is now what works for her. Instead of looking at how much she is eating in one feeding, look at how much she is eating in a 24 hour period. As long as she is getting her recommended amount of fluid, you have nothing to worry about. Also, babies tend to go through stages where they eat a lot for a couple of weeks and then don't eat as much for a couple of weeks. You will usually notice growth spurts within those cycles. Try to get in a routine and stick to it as much as possible. This will help her regulate how much she eats and how much she sleeps.

She is probally having problems breathing through her nose. Try putting a vaporizer in her room, and putting some baby vicks on her. Use a snot sucker before you feed her to clear her nose. Having a cold will make them stay up all night. I tried the cereal thing with my son and it didnt make a difference with him, but it wond hurt to try. As long as she is drinking enough milk, it wont affect her health if it is smaller portions more often. Do you think she could be teething? That could also keep her up. Infant motrin is good for teething.

Okay a few things. Don't put cereal in her bottle that doesn't make a difference in the sleeping. My daughter was breastfeed and at 12 weeks she was sleeping from 9:30-9:30 with 2 - 2hr naps during the day.
You can put a humidifier but do not put anything in the water. You can also elevate the mattress or I just put my daughter in her car seat and that would help her breath better.
But the sleeping schedule sounds like it could be the problem and my friend just had this problem with her 2 month old and when I told her to keep him awake till 9:30 or 10pm she said it worked and she is now getting sleep at night. Babies don't sleep in long stretches so when my daughter was little I would go to bed at 8pm and at 10pm my husband would bring her in and he would go to sleep. I would feed and she would go down for the night. So her longest stretch of sleep was during late at night to early morning. Getting them on a good schedule really helps everyone in the house.