You will be fine. Just do your best to stay calm and listen to what your preceptors have to teach you. Don't wait for them to ask you to do something, just get up and do it. Get your head in the game, don't let the medic make patient contact before you do. If you show initiative, the preceptors will be more likely to "take you under their wing", and help you.
As far as doing skills, everyone misses, screws up, or forgets. It happens, don't discouraged. DO NOT though, take short cuts like some people do, for example, cutting off the tip of the finger on your glove so you can feel the vein. You know the procedures, you know the safety stuff, you know what to do when something goes wrong such and blowing the vein or something like that.
Stay calm, learn from mistakes, and pay attention.