I didn't want to be the one to answer you first, because you won't want to hear this.
It appears no one has told you to expect some rough times until you get to your optimum dose, and I hate to be the one to do it.
Thyroid hormone doesn't fix the problem the way aspirin fixes a headache. The hormone doesn't repair the damage by itself instantly; it merely allows the body's systems to begin to operate properly again, including the healing process. It takes time for the cells to absorb the right amount of hormone, and then it takes time for them to heal from the damage that has occurred from the hormone shortage that you've had over time.
Very few people start taking the med, immediately feel good from the start and keep feeling good forever. For the vast majority, it's a roller coaster ride of feeling better for a couple of weeks following an increase, then crashing again until the next increase. This can go on until you reach the right dose for you.
I can't tell you what to do about your vacation and your dose. If it were me, I'd go back to 25 mcgs. But you probably aren't going to feel too perky no matter what you decide. I can tell you, if hearing a shared experience matters to you, that I lost out on a full year's worth of special occasion enjoyment... a Thanksgiving, a Christmas, a vacation, birthday parties, and an entire gardening season... while I was getting stabilized on my med. The year following that one was better, but I still had some very rough days amid the good ones. The good news is my dose is now optimized, and I have a new lease on life.
That will happen for you too, but you shouldn't think it will be next week.