MissChicopea

3 month olds go through a major growth spurt and it can effect their sleep because they want to nurse all the time. That's normal. It's called cluster feeding. She's most likely just going through some developmental milestones. Sort of like when we're thinking a mile a minute and can't rest lol.

When DD was very little we lived right next to some railroad tracks. She eventually did get used to the sound, but what helped us was having a fan on in the room as she slept for some constant white noise.

Also, we co-sleep. We've co-slept from the beginning so I don't know how feasible this is for you. Basically when we were in bed for the night, we were in bed for the night. I didn't and don't have to get up to go to her when she wakes. I'm right there and I just lift up my shirt. Easy peasy. Especially if your little one is cluster feeding. At least you can lay there and rest instead of getting up down up down.

Babies can really cycle around at that age too. DD for awhile would make night time...day time. That was tiring, but once she got past whatever it was that was causing it, she went back to a normalish nap schedule and night time. It's never *always* the same, but there abouts.

ETA: I truly think CIO is not a great thing. I know some parents use it and say it has worked wonders but I implore you to search your feelings about it. Does your body pull toward the crying baby in an almost instinctual way? There's a reason for that, really. Your baby doesn't understand you're just trying to help them sleep. They don't understand you're in the next room. Imagine waking up in a dark room and crying out for help and not receiving any. That would be very scary! There's also a lot of scientific evidence that it can be harmful to babies to CIO.