This encounter happened when I was 11 (I am now 27). Our family owns a compound in Mandaluyong City, Philippines. This compound was an old hospital during the Japanese regime and was sold to my great-grandfather.
There was nothing remodeled except that all the ward have now been rooms we let people lease (somewhat like an apartment). It has 3 floors with a somewhat underground space (like a HUGE basement) which was used as a piggery and has a well beside it. In front of the piggery (not used anymore) were 5 small rooms.
The first floor was a small hallway which had a concrete desk in the middle and has an entrance to the basement on the left and about 4 rooms in the right the stairs to the second floor was behind the concrete desk. The second floor was a LONG hallway with 4 rooms on each sides and has a BIG window in the end with an old bathroom in the right and the stairs to the third floor in the left. Then the third floor is where we had our room. It had 2 rooms. One is ours and the other is for my uncle's. The dining table is in the middle of the third floor with a bathroom in the end of the short hallway.
As this was an old hospital we were already told about ghost stories happening. But my first experience only happened when I was 11. I was in the third floor watching TV (Dragonball) then after a few minutes I felt diarrhea coming so I had rush to the restroom. Sadly the third floor restroom is being used by my dad so I had to go down to the second floor (that restroom is rarely used, and I'll discover why in a few minutes).
So, I was in the 2nd floor restroom (mid-sized restroom with a large steel drum of water) when I heard a bubble pop up from the steel drum. Thinking that it was only my imagination, I ignored it. When I was done, I went for the "Tabo" (its a tool we used to scoop water when taking a bath or wash) to wash. After a few seconds, when I was done putting my clothes back on (my back on the drum), I heard the bubble again... This time it sounded like a bigger bubble. At that moment goosebumps and fear took control... But as much fear as I was feeling, I don't know why I felt the urge to take a peek at the drum.
What I saw is still clear in my mind even after 18years. I saw a near-naked lady who is somewhat trapped and getting drowned in the water... She is trying to rise but it seems like the water got her trapped inside it... She kept hitting the water as if it was a cover.
I was just paralyzed with terror that I couldn't move, but what pushed me to move was when she screamed... It sounded as if she wasn't in the water and was just beside me... So I ran upstairs crying to my dad and told him about what happened. As a skeptic as he was, he said it was only my imagination.