What's happening at night at this house? (See details)

Sorry for the vague question…my boyfriend is staying at a friend’s house while his house is under renovation. Two strange things are happening whenever I stay over there, and I’m hoping anyone has an idea for the cause:

1. I can’t sleep. I know it’s not simply being away from my own bed or having another body there, since I do those things all the time and I’m usually a really good sleeper.

2. Mysterious bites! Last week I woke up with a bunch of bumps (I assume bites) on my right foot and ankle. This morning I woke up with a new batch on my right side. My boyfriend is totally un-afflicted (by the bites, he can never sleep anywhere).

Thanks for any clues!

Other details: there are no annoying noises or lights, nor are there pets that could bring in fleas.