red tender bumb on the bottom region of the testicals

What you felt is probably just an inflamed sebaceous cyst. Sebaceous cysts form when a substance called sebum (the white stuff from a zit) collects under the skin because the ducts that carry it to the skin get blocked. Sebum is carries to the surface of the skin, so it can lubricate the skin. It is produced by oil glands that are attached to hair follicles and carried by follicle shaft to the surface. When these ducts get clogged, sebum cannot leave for the surface and it starts accumulating under the skin forming a cyst.
The cyst is filled with white stuff and cannot be squeezed (usually). These cysts are very common on scrotums and even penis, and they are normal and they do not need treatment. But sometimes skin bacteria can get inside and cause infection. When this happens, these cysts become tender and red and swollen and painful.
Try applying warm cloth to the cyst or take a sitz baths (a tub filled with warm water) for 20-25 mins a few days and see if the cyst opens up, so that it could be drained. Do not drain with dirty hands but use a towel or a napkin if you see that it became squeezable.
If this doesn’t help, you may want to see a dermatologist and get an antibiotic to get rid of the infection.