I need an advise about my job ...?

I'm currently working in Singapore in a company which specializes in Corporate Learning and Networking. I am igned in the Sales Dep't. My job entails me to do a lot of research after office hours over the net and any other medium there is for me to get enough leads to call for the next day. My main target are Senior Executives (CEO's, VP's etc.). I finished my two day orientation last week. Yesterday was my 1st day on the floor. Today I called in sick because I just felt sooo pressured. My former job was basically a no brainer job so maybe I just feel stressed out with the new task I'm faced with. My friend keeps telling me that this will be good for me. Honestly I'm a nervous wreck. Any suggestions/advices on this ...