I was doing a lab for a high school biology class with friends. We were sitting on an incredibly high ledge above an ocean and a massive tidal wave came. The water levels got higher and higher as the wave rushed by (which took a really long time) and ultimately we went under water. However, we couldnt leave the ledge because it was the only place where we wouldnt get swept away by the current, so we just had to sit there and hold our breath until the water levels went back down.
Translation: Since you were in a high school lab, you were probably reminiscing about your high school days and are probably missing those times, even if you don't realize it. The tidal wave is symbolic of the overwhelming feelings of the beginning of a new year. There is lots of tasks to be completed, lots of homework, and lots of new people. It can be very easy to slowly fall behind all there is to do at the beginning of the year, which leads to the water slowly rising. The feeling of being stuck on the ledge relates to the fact that we cannot leave school. Even when it is very difficult, we must continue to work.