Now that you have begun research and are keeping your schedule and are in regualr communication with your mentor, snags can occur. Sometimes (many times) the project does not go as planned. This can be because a piece of necessary equipment broke, the IRB approval didn't come in, or it just isn't going as planned. Failure is the very essence of research. When snags arise, discuss them with your mentor. You may need to redefine the project or scale back the expectations. As long as snags are openly discussed this is ok.
If you get into something that is over your head and you are struggling to understand, again, discuss with your mentor.
Know any deadlines you are given, any requirements you have, and meet them.