Stress Related Pomeranian Hair Loss?

by T
(Perth)

Hi, we have a male Pom. Took him on about 4 months ago during winter. He hasn't really shed too much hair. But recently (last week) hes been losing a lot. I run the brush over him every day and it's full of his hair. I assume he's shedding his winter coat? He not going bald or anything, but keeps scratching and walking around with bits of hair hanging off him. When we took him on 4 months ago we had another dog who he ended up being inseprable from. Unfortunately the other dog was run over about 2 weeks ago and I worried that our Pom is a bit stressed and his hair loss may be linked to this? He's off his food too. Anyhow if anyone could let me know if its normal for a 4YO sterilised male Pom to shed his winter coat.