MIL driving me crazy with my newborn?

Ok so this is my third baby, but her first grandchild. I know how to take care of a baby and I know the current do's and don'ts. The last baby she raised was 27 years ago. Anyway I finally got her to stop putting him on his belly which was the first issue I had. She swears he NEEDS to go on his belly because if he spits up he will choke. I told my bf who was actually listening to her that more babies die from SIDS than they do from choking and that our son is breastfed and hardly ever spits up anyway. He finally started listening to me when I asked him if he wold like the doctor to explain to him instead. Other than that it's been a bunch of little things until now. He is almost 7 weeks old. I try putting him in his crib as much as possible to get him used to it, but in the middle of the night if it's not working he goes in his swing or his bouncy chair. Both of them are in a reclined position. We live with his parents right now because before I came along there was no point of him having a place. He is a truck driver and is only home 1 or 2 days a week. Also last summer both his parents needed surgery and were out of work so he was the one here paying the bills. Now we are saving to buy our own house. Anyway she keeps lecturing me about how I need to put him in his crib blah blah blah. Come on! I have a 2yr old and a 4yr to deal with on top of taking care of my newborn I don't need you NAGGING at me! Both of my other kids were raised by me. Both of them slept in a crib from about 3-4 months until they no longer needed it. Both of my kids sleep in their own beds to this day. I think I can handle it!!! In my opinion I should be doing what works for ME. Am I right? During the day I try all day to put him in his crib and maybe 1 out of 10 times he actually stays asleep in it. I will try once in the middle of the night and after that no because I am lucky if I get 5 hours of sleep on any other night. I got him to sleep in his crib from 11pm to 3:30am last night, but when I put him back around 4:30 he wouldn't stay asleep so finally around 6 I put him in his swing after he woke me up every 20 minutes. She doesn't work today so when she woke up and saw him in his swing she started the nagging again. What would you do or say? Am I wrong? I think I'm right because my other kids are just fine. I keep explaining how he won't sleep and I need to sleep, but that doesn't work. I'm going crazy!