Is calling someone "uptight" an insult?

[Inajobrut]

I have just asked my husband why he is being so uptight and he had a massive go at me. Tells me I insulted him.
English isn't my first language, so I'm really puzzled. In my mind I didn't say anything wrong, I just told him to relax in a calm manner.

We just spoke and both apologised. Exactly like everyone said he explained why he got frustrated but apologised for overreacting. I understand his perspective.
Our relationship is really good but for a number of reasons we are both going through a tough period in our jobs, so feeling a bit tense. Agreed to be more understanding to each other.
Thanks all