A lot of people have difficulty running against headwinds. They have problems, because they try to maintain their no-wind pace. To be successful as runners, we must be flexible such that we adjust our training to meet the problems we encounter.
We may leave home not expecting a headwind, but as soon as we discover there is a headwind, we should adjust our training accordingly. Headwinds are like hills. They try to push us backwards. It takes energy to overcome the headwind and make progress in the other direction. Thus, unless we have a lot of energy to spare, we can't expect to run at the no-wind pace. The common-sense thing is to slow down and not waste a lot of energy fighting the wind. During the first half of the run, I did slow down, and I felt comfortable while I ran against the wind. I wasn't frustrated because of the wind. I just accepted it and adjusted my pace accordingly. Similarly, on the way back, the wind was now a tailwind, and I felt comfortable even though I was going about 30 seconds faster.