Lea Michele's latest public appearances have prompted a lot of questions and concerns.

On Sunday (Oct. 20), the 'Glee' star was spotted at LAX wearing a never-before-seen diamond ring -- yes, on that finger. E! News has posted a photo of Lea at the airport, with a closeup look at the ring (see it here).

The singer-actress was returning from a weekend trip to San Francisco with friends Jonathan Groff and Skylar Astin. She posted a cute photo of her and the guys on Instagram yesterday (Oct. 21) with the caption, "Back from an amazing weekend in SF with these boys!"

This looks like a great time with good friends, so we don't think that the ring came from one of them. While the mystery of the ring has yet to be solved, sources have confirmed that it was not a secret engagement ring from her late boyfriend, Cory Monteith.

Meanwhile, Lea's gaunt appearance last night at Elle magazine's Women in Hollywood event has sparked fears that she hasn't been eating properly since Monteith's death in July. A source seems to confirm the speculation to HollywoodLife: "They want to make sure that she will eat, since that has rarely occurred since the news of his passing."

Lea does appear to look very thin in photos from the event, even in the ones she posted herself:

Take a look at the ones below and let us know what you think. Should we be worried about Lea's health?

Is Lea too thin or is it just the cut of the dress?

Michael Buckner, Getty Images

A view of the back -- too skinny or just fine?

Michael Buckner, Getty Images