Well it shouldn't mean much BUT just in case keep away from snakes have a great day :)
Nothing
A snake in dream represents a person who lives in a valley. A snake in a dream also means enmity from one’s in-laws or children, or it could represent the evil and jealousy of one’s neighbor. A sleeping snake in a dream means a sleeping enemy. As for an unjust person, a water snake in a dream means receiving help, or it could represent a verdict. Owning a snake in a dream means gaining power and authority. Its flesh represents enemy money, or it could mean joy. If one sees himself wearing the skin of a snake in a dream, it means that he will unmask his enmity toward others. Killing a snake in a dream and staining one’s hands with its blood means destroying one’s enemy. A snake in one’s dream also represents a rich enemy, for its poison means money. If one sees snakes being killed in the streets in a dream, it means a war. source: islamicdreamguide . com
The snake is representing someone that you know in the real world.
The snake represents a problem or perhaps a person who is aggressive and seems to threaten you. A brown snake would be difficult to see against dry ground or rocks, suggesting that you have difficulty seeing exactly what this person is doing. Note that the dream depicts your own suspicions and discomfort; it does not provide any proof that the situation or person actually is aggressive or dangerous.
From my own understanding, snake means someone doesnt like you.
See a psychologist.
Snakes mean temptation, evil and deception - usually someone you don't trust etc. If you have caught the snake and placed it out of harms way then you have solved the issue with someone you dont trust or is deceptive towards you. Usually if you dream this then you are the bigger person and can control the situation.
In this particular dream, the snake probably is a symbol for something untrustworthy or repulsive. Seeing the ex-boyfriend with the snake, it suggests that those feelings are associated with him as well.
In this dream, the snake probably represents a problem that the dreamer fears will affect the son in some way. The dog represents protection, and is the first solution tried in the dream; "can I protect my son?" The sock might represent hiding (ignoring) the problem or it might be a play on words: "can I sock this person who is troubling my son?" When the son is playing with the snake, the dream is considering whether the problem is really as dangerous as feared. This type of dream allows the dreamer to experiment with various ways of approaching a problem while in the security of sleep.
Every dream is about the person having the dream. So this dream of your double is about the person that dreamt that dream, not about you.
To see a snake or be bitten by one in your dream, signifies hidden fears and worries that are threatening you. Your dream may be alerting you to something in your waking life that you are not aware of or that has not yet surfaced. The snake may also be seen as phallic and thus symbolize dangerous and forbidden sexuality. The snake may also refer to a person around you who is callous, ruthless, and can't be trusted. As a positive symbol, snakes represent transformation, knowledge and wisdom. It is indicative of self-renewal and positive changes.
If that is what you have dreamed, don't worry about it. I can assure you, DON'T WORRY! nothing should happen.