I know it is hard but do not be put off by the one, two, three or four know-it-alls who like to assert themselves by subjecting PhD students to a barrage of nonsensical questions. They want people to hear them and if they are unreasonable most people sitting in the room will see what they are doing and definitely not think it is big or clever. I would do the presentation. Remember even in the 1st year nobody knows more about your work than you do. Stick to general background, questions of methodology and ask for advice on future directions. I am almost finished and I am still wary about presenting my substantive findings - not sure you know what you have found until you send the damn thing off to the binders. I would go for it and ignore the idiots who have to put people down to get heard!