I accidentally deleted some photos recently, and have used multiple recovery programs and i can find very old ones but not the most recent. any ideas why?

I'd recommend that you try asoftech photo recovery which is one of the best photo recovery program, download the program from
http://download.cnet.com/Asoftech-Photo-Recovery/3000-12511_4-10913438.html?part=dl-10913438&subj=dl&tag=button

Probably you should download a photo recovery utility that will recover your pictures with this software called Wondershare Photo Recovery (I once used this program bounded with some other software) from the following link(the program also recover videos and music files):

Photo Recovery for Windows (if you are running Windows OS)
Photo Recovery for Mac (for Apple Mac OS X)

Remember - Do NOT try & write anything back to your camera(memory stick) until you can recover the files safely!

Have you tried this speacial photo recovery software? You may rely on it.

Remember - Do NOT try & write anything back untill you can retrieve your files safely! I hope you good luck. Best regards.

Yes. Instead of wasting time on manual ways. There is software that totally Recovers Deleted Photo, music, and videos from local PC and multiple devices. Yes absolutely. There are paid services. But if you are looking for free software. I am putting a link below. It helped me. https://www.stillbonsoftware.com/photo-recovery/

If the photos were overwritten by new ones, there is no way to get them back.