Farrah Abraham Is Not Engaged Despite Online Speculation After Flashing Ring

Farrah Abraham sent eagle-eyed fans scurrying to cook up engagement rumors after she flashed a huge diamond ring on social media ... but TMZ has learned she's NOT someone's fiancée.

Farrah set off the frenzy when she included a couple photos of her with a ring on THAT finger in a recent Instagram photo dump ... including one snap where she's pointing to the bling.

The ring also popped up in a mirror selfie ... and Farrah further added to the engagement speculation when she mentioned "winning in life" and being thankful for her "birthday surprises" in the caption.

However, our sources tells us ... Farrah is NOT currently engaged.

Eagle-eyed fans also noticed what looks like a pregnancy test laying on the bathroom counter of one of her selfies.

We reached out to Farrah's rep, who tells TMZ... "We've seen the rumors and understand the interest. Farrah has something very exciting to announce and is looking forward to sharing more details soon. At this stage, we're not confirming or denying any speculation."