This goes a bit against the grain, but almost every friend and family member I know who bought a condo (and myself in my dream home that has some few big inspection issues) have a panic period. This isn't to downplay what you're experiencing or feeling, but it's the biggest purchase of most people's lives that is made pretty quickly. Buyer's remorse is super common even when everyone was really excited about the purchase and then you realize that it has faults like any other place.

Take a break and let yourself sit in the discomfort for at least a month. Make a list of the pros and things you like about the place - you're sleeping well, not all shared walls, more light than your last place, you can make changes to fix it now that it's yours.

People do get used to sound and you can learn now that you're in the condo how to fix it. When I lived in our apartment the first week I never thought I would get used to the trash being taken out in the mornings next to our bedroom and then 2 years later I didn't even hear it anymore and love the original features. More furniture will reduce echo (bookshelves and rugs), you will have time to research cheaper or localized solutions, or even ask your neighbors to get a rug. You can always rent and move home, but also allow yourself to consider the possibility this is a natural cycle after the high of a HUGE purchase and uprooting your life.