For several weeks now i've been feeling some nausea before i go to bed and a LOT in the morning before i eat. Could this be caused by a slow gall bladder ? From what i've figured, the nausea (usualy but not always) starts when the stomach is empty. Could it be ulcer ?

What is very frustrating about it is that the more nauseaous i am, the less i can eat !!!
I recently had an Echography, blood & urine tests and they all came out good-ish.
Any ideas please