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Probably not. Rabies vaccines will cause some localized pain and a general sick feeling for a day or so, but it usually does not last for more than 48 hours.
I would feel led to think that you are dealing with a parasite problem or other issue instead.
If you have not seen the vet for an exam recently, I suggest that you do so in order to rule out parasites, giardia and coccidia as the cause.
Let me know if you still have questions.