First, do not worry. As KingSlayer said it is just an ingrown hair or a pimple.
It will pass on its own within a few days, practice good hygiene and do not wear tight underwear.
Didn't see any black spot on the picture just a pimple.
As to the rest if it will still bother you in 2-3 days visit an urologist and he will tell you what to do with it.
Best wishes, John.
P.s. use of any anti pimple cream may also prove to be useful.
Looks like some type of ingrown hair bump. You can try a drawing salve on it and cover it with a bandage. Keep it as clean as possible and covered to reduce friction against it until it heals. I do not think it is anything serious. The drawing salve you can purchase from a pharmacy. If it is still not getting better, try to find a physician that can look at it; not necessary to go to a hospital for this at this point.
The best.