Would I be safe to assume that each to-go is 5 mcg per spray? Also, how do I do a half spray? I see people say things about 2.5 mcg, and I’m not sure if there is a specific technique?
No - it varies between products and strengths. The basic info for mcg in standard products is on each store page - and the togos are approx 80% of a fullsize/30ml spray.
Doing a half spray is a matter of careful finger control on the plunger - pump it lightly a few times till you feel the fluid pressure against the pump mech, then execute a short controlled press. you soon get the hang of it.