Am I on the hook for windows?

In March, we found out our neighbor works for a window installer, so we asked for an estimate. He gave me a ballpark for the whole house, which I said sounded good, but I would want just the front elevation and two in the back, since we are having remodeling done in a year or so in the back, and don’t know what style we will end up with.

So I had him measure, which is typical before an estimate, but I never heard back with an estimate except a short email in April that his supplier was "working on the order." I assumed he meant the estimate. It had been awkward because of the long delay, so I thanked him for the update and moved on. This week, after waiting six weeks and hearing nothing, I found an installer I liked who gave me a detailed estimate in an hour after measuring.

I wrote to the original guy that since I hadn’t heard anything, I wanted to make sure he knew that I would be using another contractor, and he dropped a bombshell that he’d ordered windows and they were shipped?! I don’t even have a written estimate of the cost, let alone a signed contract. It was such a shock! My husband had been there when he measured, and the contractor wrote to me he thought he had “explained everything to him.” My husband was baffled. He was just there to guide them to the windows to be measured. The contractor certainly didn't mention an estimate - even verbal. We have no idea what they will cost, or what the specs are for what they will look like.

Help. I don't want to have a bad relationship with my neighbor. I was worried at first that it was a bad idea, but he works for a professional company ... I thought it would be a professional estimate, by the book, etc.