HR total in single game stats
 

how come after a game is played and i am looking at the box score afterwards it seems to include a players hr total instead of if he had one or not that game? For example, Jason Heyward my last game was 1 for 4 with one RBI and a walk. Then under HR it shows 3. If that was the single game total he should have at least 3 RBI if he had 3 HR in the game.

The 3 HR in the boxscore on the player's line is his HR total for the season. If he hit one in-game it would show down below where the hitters are listed where it shows who hit doubles, or triples, or homers, or stole a base or made an error etc.

The stats listed to the RHS are cumulative; they show the players stats up to and including the game just played.

See this. The player top right had 1 HR and 39 RBI before this game.