Oh, comma splices, how I’d miss you if you stopped showing up in stuff for me to edit…
There he was again. This was the second time I had seen him, and he looked exactly the same as before, but the first time had been twenty years ago. I thought I was the only one. Now I wonder how many others there are like me.
Stating that you wonder something is not the same as asking a question. Do not end a statement about curiosity with a question mark. (You could write it as, Now I wonder, how many others are there like me? Flipping the order of are and there, plus adding a comma to separate the declarative from the interrogative, makes the latter part a question needing a question mark.)
I do like the “plot twist” at the end of that paragraph, though. I think… (*mutters something about small Romans*)