The possible reason for the symptoms you are experiencing are the stimulation of the different parts of the brain that occurs as a result of the act and perhaps, your desire to conceive. It is a natural phenomenon and nothing to worry about. The natural hormone oxytocin
released during the process could cause the nausea
. Do not stress
about this and consult an infertility
specialist to get investigated for the treatment of your infertility problem. Good luck.