The singer had just crossed from Kansas into Colorado when he got the worst welcome ever.

SOMEWHERE IN COLORADO - Just one day after triumphantly crossing the Kansas/Colorado state line, singer Mike Posner is in a Colorado hospital. The culprit? A baby rattlesnake.

The “I Took a Pill in Ibiza” singer posted a video from his gurney on Thursday and seemed to be in good spirits even though the injury is setting his walk across the country back several weeks.

“Whatup doe!!! Crazy day yesterday!” Posner’s Instagram post reads. “I had just crushed 16 miles and was gonna do another eight when I got bit by a baby rattlesnake! That venom is no joke!”

Luckily, Posner was airlifted to the hospital and received the antivenom in time. He had a “special shoutout” for nurses Bo, Cassie and Whitney, and said he’ll be spending a few days in the hospital recovering. He said he can't walk for a few weeks, but is enjoying having air conditioning and a nice bed.

The 31-year-old singer is a few months into a walk across the U.S. His journey began in Asbury Park, New Jersey, and he’s been walking 10 to 15 miles a day with the ultimate goal of reaching Venice Beach, California. He said the trip was inspired by the death of his dad as well as the DJ Avicii, who inspired the lyrics to one of his most well-known songs (“I took a pill in Ibiza, to show Avicii I was cool …”).

After he posted about his hospital stay on Instagram, multiple celebrities offered Posner their support … including Ryan Tedder, the lead singer of Colorado-bred band OneRepublic.

“Dude don’t ever talk to snakes,” Tedder commented.

Good advice, for what it's worth.

Joe Jonas also expressed his concern, writing, “Rest up bro. Glad you are ok.”

Jessie J called Posner a “real-life superhero.”

When Posner crossed into Colorado on Wednesday, he was walking on a dirt road in the Eastern Plains – specifically “Road N” and “Road 39.” While this can't be confirmed, this pin appears to be the location of Posner's Colorado border crossing per this intrepid journalist's scouring Google Maps.

“Ain’t no ‘Welcome to Colorado sign out here,’” Posner said.

He is definitely right.

We wish you the best in your recovery, Mike! You’re cooler than all of us.