My 63 year old father cried when I returned home, is that okay for a man?

Probably not seeing you for a long time softend him up (happens a lot) also your mom just died women are usually the emotional ones and not having her to talk to made him bottle everything up inside. I don't think anything is wrong with him psychologically just he bottled up his emotions for a long time, and when he saw you it made all his thoughts and feelings burst, because he hasn't seen you for such a long time all the emotions came out of the bottle.