No, you are not allowed to withhold rent from the landlord without an order from the court or written permission of the landlord and you are required to submit all request for repairs in writing.
In Georgia the landlord has an obligation to keep the rented premises in good repair during the tenancy unless there are specific contractual agreements to the contrary. (O.C.G.A.  § 44‑7‑13). In a residential tenancy if the landlord allows the property to fall into such a state of disrepair that it becomes unsuitable for the tenant's purposes, the tenant becomes "constructively evicted" and owes no further contractual obligations to the landlord.  Once the tenant notifies the landlord that repairs need to be made, the landlord must inspect the property and make arrangements for the repairs.  If the tenant gives the landlord notice of a defect and the landlord fails to repair within a reasonable time, the tenant may make the repairs and deduct the cost of those repairs from rental payments.  However, a tenant may not withhold rent merely because the landlord fails to make repairs, unless there is a constructive eviction.  If the landlord's failure to make repairs damages the tenant's property, the tenant may recoup the amount of those damages from the rental payments.  The tenant has a duty to use ordinary and normal care and diligence to prevent injury or damage to the property.  Included is a duty to notify the landlord of any repairs needed and to make it possible for the landlord or the landlord's agents to have access to the property to make those repairs.