I'm afraid there are a lot of errors. There is also insufficient information. The first sentence could be improved by writiing it as:
My two days experiece at the Veterans Home were wonderful.
But it would be better if you could explain why you were spending two days there and what exactly you were supposed to do. Something like this:
My two-day assignment as an assistant caregiver at the local Veterans Home were wonderful.
You shouldn't call the patient you were assigned to work with a "guy," and the word "sweet" seems inappropriate. Try writing something like:
The elderly patient I was assigned to help was friendly, grateful, amusing, and interesting.
There is no such word as "gonna," although you sometimes see that in dialogue in stories and in subtitles in movies. It should be:
I'm going to miss him.
I think it might be more truthful to say:
I'm sorry I didn't get to spend more time with him.