Is it possible to have more than 1 viral disease at the same time? with one of those being mono

Yes and no: Some viral illnesses like hepatitis have a specific location of action and a long course lasting months or years. Others like colds are transient and invade common entry areas like the upper airway. Many viruses induce a substance called interferon that tends to repel new viruses while you have one in place, but this fades so you can get a new virus.Bacterial infections are common co-infections.