With the mid-season finale of The Vampire Diaries  (Season 5, Episode 10 — “Fifty Shades of Grayson”) quickly approaching, we’re gearing up for what’s sure to be an epic cliffhanger. Not to mention the fact that this will be the last episode until the milestone 100th episode airing in January when the CW series makes its return from hiatus. But what’s happening in this Thursday’s episode?

As we zoom in on Matt Donovan (Zach Roerig) and Katherine Pierce (Nina Dobrev) getting their fitness on — well, trying to — it becomes evident that Katherine’s rapidly ticking biological clock is catching up to her.

“Good try,” Matt offers up to the frazzled Katherine.

“Good try? That was horrible, Matt,” Katherine retorts. “I’m paying you to make me hot again, whip me into shape, and prolong this death thing as long as possible.”

Then, after Matt makes a snarky aside, we realize just how bad Katherine’s body deterioration actually is. At first we think she’s just getting sassy with her fellow human, but then we’re faced with the harsh reality: she’s dying faster than we had thought.

“Oh my god, I’m going deaf,” Katherine exclaims. “My entire body is falling apart.” Yikes, sounds like Katherine is losing it — physically and mentally.

After Matt — in his all-American charm — offers Katherine some water, he suggests she take the easy route and just become a vampire again, though that idea is quickly shot down.

“Everytime I ingest vampire blood, my body rejects it,” Katherine reminds him. This is not good, TVD fans. We might be losing Katherine quicker than we thought.

Could our worst fears be imagined? Will Katherine die soon? Hit the comments and let us know what you think!

The Vampire Diaries airs Thursday nights at 8 p.m. ET on The CW.

Carson Blackwelder is an Assistant Editor at Wetpaint Entertainment. Follow him on Twitter and Google+!