Could i be coming down with the flu, and should i do anything about it at the early stage while around immunocompromised family?

Maybe, and yes: I have no idea if you are coming down with the flu, but if you are around immunocompromised persons, you can help them by washing your hands religiously, using hand sanitizer if you can't get to a sink, and don't share utensils, drinking glasses, door handles, etc., it might also be appropriate to use a mask while you have symptoms of the flu. They too, should practice good hand hygiene.