M.W.
OMG! And I thought I was the only one. Seriously the same thing happened with my daughter right about that time. She was previously sleeping through the night (in my bed) and got that drunkard look when she was done nursing. She's 6 months now and it hasn't come back. I was so afraid I was losing my milk supply. I contacted La Leche and read some books and heres what I learned:
1. Around 4 months your milk supply does sort of plateau in that when the baby is young you usually over produce and later your body produces just what the baby eats. This is ok and normal. If the baby needs more, she will eat more often and you will produce more. I think my daughter could drink a gallon of milk if I had it but she doesn't need it.
2.Your let down relex gets slower, I know this is part of what was frustrating my babe, causing her to whine and pop on and off the breast. This is also ok and you should try to relax and let the baby do what it wants to "milk" your breast. This includes any hand action she might be doing too.
3. Teething can interfere with nursing way long before any teeth peep through so when all else fails blame the teeth not yourself.
4. It is not necessary or recommended for breastfed babies to eat anything else for the 1st 6 months. That young they are really not capable of digesting and extracting nutrition from solids and any food you give her may displace breastmilk from her diet so in the end it could actually lessen the calories and nutrition she is getting.
5. Nightime nursing is one of the best ways to increase your milk supply and some babies get the majority of their nutrition at night. I know mine did bc at night she was half asleep and patient enough to suck steadily and stimulate a let down.
After reading all that I also looked at my life and yes, I too was way stressed, not drinking enough water, I had cut back calories cuz I wanted to lose the baby weight asap, and I was not sleeping enough.
The baby was in my bed at night since birth which had worked fine but it seemed like overnight she stopped sleeping. So I skimmed through Dr. Ferbers book and the No Cry Sleep Solution. I ended up doing a combo of both. I gave her regular nap and bed times and implemented a sleep ritual. I got her to stop nursing to sleep even though it is still a part of the sleep ritual.
She would cry 5 minutes at a time and I'd go in and shush her, pat her anything except pick her up for 1 min. For a few days I had to do this 3-4 times with each nap then she started to get it. She still lets our a few wails now and then (not even lasting 1 min) but she sleeps for 4-5 hour stretches, I can nurse her and quickly set her back in her crib at night and I get at least 2 1.5 hr naps.
Sorry that was long but I really hope someone can learn for what I went through. It was hard, I was hysterical all the time. Check out those book (I found them at the library), take care of yourself and be confident that your baby will ask for what she needs. We just had our 6 mo appt and shes a lil over 14 lbs, the doctor said she looks great, people tell me all the time that shes so small but she is happy, healthy, and developing great. So keep your head up!