Yes, room should be alright however air circulation may pose a problem. If I'm understanding correctly, you want to use the bottom cabinet of your bathroom sink (which is fixed to the bathroom sink) for your grow? In most cabinet grows they're modded to allow cool air from outside into the cabinet as well as built up hot air from inside of the cab, out. Wondering how you plan on handling this when heat becomes an issue, assuming it will. I would setup your lights and take temps over time as well as humidity to see what numbers you get.
