My Grandpa Came Home From The Emergency Room Earlier Tonight

My grandpa came home from the emergency room earlier tonight and he went it because he was having dizzy spells and actually fainted out in the front yard. Earlier at 10:20 PM MST his blood pressure was 139/91 and now one hour later 11:20 PM MST its reading 87/56 is this normal or does he need to go back to the ER. He has also been throwing up since he got home earlier.