(Let me start by saying this story is from an actual lucid dream I had long before my little pony, what would cause me to have such a dream, I have no idea, I still remember this dream clearly as though I just had it.)

A long and dusty road lay ahead, to where, I am not sure, but I could not just stand here, in the middle of nowhere and think about it, I began to travel along the road, and as I did so, I came upon a stranger.
We began walking along the road and making light talk, I did not know the danger I was in.
Finally he said simply: "you know, with a horse we could travel faster"...

I could only agree...

The trap was sprung...

A strange chuckle emanated from the stranger and next thing I knew, I was a white horse, a Mare, who then mounted me and rode me into the town to which this trail led, where upon he turned me over to some other person and collected some coin, then turned away heading for a tavern.

I think I was just sold to a farmer.

I was now ushered to a stall in some barn and left to my own devices, it was a cold night, so a horse blanket was placed over me.
Then, as horses go, I feel asleep on my hooves.

My life became pulling a plow each spring, or being ridden to town for supplies, or pulling a cart. though the Farmer did care for me too, I was fed and treated very well.

One day, the farmer bred me to a black stallion, what an odd feeling that was, to be, how shall we say, taken by a Stallion, no ceremony, or foreplay, just taken.

And then back to the routine of plowing, pulling a cart and so forth, and with each passing day I grew heavier with the weight of a foal growing inside me.

one day, I began to experience pain, deep inside. My body began to convulse with the contractions of birth, waves of more pain wracked my body with each contraction, I was giving birth.

The farmer and his wife were there with their daughter attending the birth, he and his wife were explaining what was happening to their daughter. Soon, the little filly plopped out on the floor of the stall, I turned to look at it, motherly instinct overrode any other thoughts, I began licking the little filly clean and dry, afterbirth leaving a salty taste in my mouth.

The little filly was brown, to my white, upon her face a white star, I named her "Star" for her face, as she rose and began nursing from me.
Which was also a rather odd feeling, I was growing more and more confused as to what was happening to me.

My mind began to protest this reality, I knew I was once human, I had to be human again, my reality began to distort....

(This is where I awoke from the dream, but today, I still wonder about that poor little filly, and this strange dream that seemed so real, I hope someday to see her again, maybe in my next life, I will be a Pony and see my filly again).

Interesting dream... I've no idea whether you might be an actual horse therian, but that might (maybe) explain? I dunno.