bad sleepover, what do i do? how can i be nice about it?

so i, 22m, went on a sleepover with a guy, let’s call him issac, 19m, and some of our other friends.

now, when we finally went to bed after playing video games, and i was starting to get tired, we decided to go to our rooms.

Issac said “gb19 will sleep on the inflatable mattress of my room, you two sleep in the guest room.”

i got on the mattress and was falling asleep, but felt issac staring at me. the next time he did it, he leaned in closer.

“Are you asleep yet?” He asked.

I said “no. What are you doing?”

“I want to make sure you’re at home in my house.”

I lay down again. when i woke up at 3am, i felt something brush against my face. i reached for my phone on the floor, using the light to see what it was. what i was holding appeared to be a small square paper thing.

it was a picture of issac. On the back it said, “I’ll always be here for you. XOXO Issac.”

Is this some big prank? What do I do? I’m scared as hell.