Yeah, I suggest that you solve your cube several more times. The first few times are always the slowest.
Also, what do you do after you finish the corners?http://youtu.be/Alz5t_OR47I?t=15s
It looks like this is your method. Also, lookahead means to look for another piece while solving one so that there are no pauses in between performing the algorithm and finding the next piece. (Multitasking)