Well, it is possible that when you deleted the video, more was grabbed. Or even that the video had overwritten the photos and that caused the problem. However, are you sure the photos were actually on the SD card? To check, pulling it from the phone isn't the best option. Try connecting the phone (while the card is still in it) to a computer via USB cord. Search the card and the phone for the photos. Sometimes the image files won't show if you just use the card in a different device. Especially if the card was encoded or formatted differently.
If you can't find them this way either, then they are probably gone. However, you can try some recovery software and see if you can get them. No guarantees.
There are a few apps/programs out...