I don't really know. Do people usually just permanently feel all warm and fuzzy after a pleasant encounter? That would seem strange to me. I really enjoy spending time with my sister, but I would find it strange if the feelings I get from that lasted until I next saw her. I think it is pretty normal to miss people.

When I have heard people talk about object constancy, they have felt like the therapist just didn't exist somehow. That doesn't seem to be the case with you. It sounds like you felt connected, that feeling faded after several days, and now you miss the feeling of connection. I don't think that has anything to do with object constancy, but I could be wrong.