Can I get my photos back onto my phone ?

Hello, I have a question about my iPhone. So yesterday, my iPhone had backed up all of my photos from my IPod that was in iCloud onto my phone and I had 1500+ photos. I didn’t want to delete the photos from the album because I thought it might delete all the pictures out my IPod too so, I went to the settings clicked the iCloud Photo Library thinking it would just remove all the photos it synced but it deleted basically all of my pictures out my phone and I’m now left with only 145. I see when I click on storage it says I have 5.8 GB worth of photos but I know 145 photos wouldn’t be taken up that much storage ??? So I was wondering are my other photos still there and is there a way for me to get them all back onto my cell phone ?