Looks like a tiny Die Break/Chip. Not a cud nor doubled die. Nothing really major. BTW.. Cuds involve the rim and flow into the field. Here are examples from my collection. Anything else is called a Die Chip.
Brandon, the coin you are showing is a pre-1982 cent, which was mainly copper and being a soft metal, it is easily moved when struck. I believe the 7 took a hit that flattened the leg. The MM appears to be from a worn die, so not an error. So, nothing more than wear and PMD, IMHO
Not a cud as they must touch the rim. To me it looks like the bottom of the 7 took and hit as it’s been flattened.
You can't have a cud on both sides. The area on the opposite side of the coin from the cud (raised metal) will have a void area (or a lightly struck area). If you are referring to the quarter Paddyman98 has shown, the obverse has the cud, the reverse has an incuse area of missing metal.