'Bachelor in Paradise' Star Corinne Olympios 'Falling Over' Drunk Hours After Pool Sex

Corinne Olympios was so wasted several hours after she and DeMario Jackson hooked up, she could hardly stand.

Witnesses at the Mexican resort tell us 2 hours after her sexual encounter with DeMario ... she was stumbling drunk, eyes closed, slurring badly and wearing her clothes inside out. As one source put it, "she was on a whole other level."

TMZ broke the story, a week ago Sunday Corinne and DeMario were naked in the pool, "rubbing, touching and fingering" and engaging in oral sex.

As we reported, Corinne insists she was so wasted she was incapable of giving consent, and blames producers for not calling a halt to the escapade. She says she has no recollection of events in the pool.

People who have seen footage of the encounter tell TMZ it's apparent she was lucid the entire time.

We know DeMario says when they went to the pool, Corinne was drunk but still lucid.

Connecting the dots ... it's possible Corinne was drunk but still with it at the pool, but as she continued drinking entered a blackout stage and forgot most of what happened from the time she began drinking.