I have started my PhD a month ago, and am a little worried about the progress I'm making. Although I have been working hard, I've made a couple of silly mistakes during the lab work, and as a result, my project is a little behind. I have also hardly spoken to my main supervisor, as he is always very busy and I'm worried I don't seem very enthusiastic about the work I'm doing because I'm very quite during lab meetings. I hope I won't be sacked. What shall I do?