Sci-Fi short story.

Note: I am not the author of this, but he gave me, and only me I would like to point out, permission to copy it here to see people's opinion. It is by an (as yet) unpublished author, but if he ever gets published i will say what the book is called, and his name.

Yes, it says 'I' instead of 'me' constantly. I have never figured out why.
So, what is your opinion:

Doubts

He first appeared when I was studying the effects of gravity on space-time. A man completely in black; black coat, black shirt, black trousers, black socks, black shoes, black hood covering his face.
He simply said all of my doubts and fears; he knew I better than I knew myself. I was forced to stop my work.
I never saw the man again.

Until, of course, I began work on singularity, black holes, and its effect on time. The man reappeared, this time openly commanding I to stop.
I did so, terrified of this strange man. He could tell I almost anything about myself; he knew my fears.
My rival scientist discovered something groundbreaking a single day after I stopped; he was studying singularity, the same as I.
The man in black had stopped I achieving this.

I wouldn’t be stopped this time. I was almost out of money and prospects, so I went for something huge.
The man in black appeared again, shouting, crazed, by now. I did not stop. I would invent time travel. With that created by I, they would forget about my rival.
I did stop, however, when the man in black lifted his hood.
I stared into my own face.