“PPD” can take many forms at many levels. Lack of sleep can be a huge trigger for at least the “blues.” And crying for no reason, even though you are fine in between is definitely at least the “blues.” I’ve BTDT many times over to varying degrees (B”H never needed meds). You need first and foremost sleep! Let your husband give a mid-night bottle or two. Work out the best time for both of you. You need a good stretch of sleep. Even if not every night. Your nursing won’t suffer for it (if you were concerend about that).
Household help can be tough if finances are tight – teach your husband what a broom and a mop are, and even your big ones can fold laundry (so its not perfect, big deal). Let your friends send over suppers (that was a lifesaver for me – we all got a square dinner at least). And send your toddler to a babysitter for a couple of hours a day so you can catch a nap.
Mazal Tov and hatzlacha!