UPD Back to back Classes

Helloo! I'm an incoming freshman, and our pre-enlistment just finished. Looking over my schedule, I noticed that I have three consecutive classes that are back to back with no breaks in between. My main concern is whether I'll have enough time to get from one building to another before my next class starts. Are profs usually understanding if you're a few minutes late because you're coming from another building, or is there a grace period before classes start? TYIA!!