Swollen eye on 7month old

[SuzyP36]

Ds went to sleep last night in his own room for 1st overnight sleep, been going in during day for past few weeks for naps.
Anyway he sleeps well but woke up with a swollen eye and I felt slightly swollen cheeks.
Phoned nhs24 who said as there was no fluid etched coming from it just cold compress it.
Swelling has went down as day went on but tonight I feel he's been more unsettled.
Don't know if I'm just over thinking it now tho. Still don't know why he woke up like this but he did sleep on that side which he's never had the chance to do before as his crib was too small for that.
Just wondering if anyone has had a similar experience as now I'm actually worrying about him sleeping tonight in case his throat swells up or something irrational like that

If it looks swollen tomorrow, take him to the gp. It could be an eye infection. When DD1 was about 1yr she woke up one morning looking as if she had been punched in the eye! Her eyelid was so swollen it was almost totally closed. No discharge from her eye, it improved a little with Nurofen. I took her to the gp, thinking she must have some how bumped her face in the night. Gp said it was an infection. It was treated with eye drops.