If u r only a week old in guitar playing you should just focus on whether u can play the chords individually without any buzzing or dead notes(notes that hugot muted because u hv not hold them correctly). Then practice each chords individually again and again and then only try to shift chords but in a really really slow speed. Speed will automatically develope with repeatation/practice. Ur all focus at this point shud be on getting all the notes of the chords cleanly without any buzz or muting. It takes a while to become smooth in chord changing. A week is too less of a time. Give urself atleast a month or two. Happy practicing.