Please help!

Hi everyone! So I recently bought an ipod touch. I have an older model of ipod touch but its starting to fall apart, hence buying a new one. I have loads of songs on the old one that I’ve been treasuring for over 10 years. I did back it up on my mac, thinking everything will be save there so it will be ready to transfer to the new ipod. So I set up the new ipod, restore it from the old ipod only to find out that the songs that have been transferred were the only one I bought off itunes, while other hundreds didnt. So i plugged in my old ipod again, songs were there but cant figure why they didnt transfer so I ended up doing auto music fill and I accidentally replace all those songs with just the songs I bought off itunes so now all those hundreds of songs have been wiped off, and I’m trying to find a way to get them back. If anyone knows how to do it, please help me. I am devastated! 😭