First stop for any questions about numbering is always Shauna Kelly's pages – try http://shaunakelly.com/word/numberin...numbering.html

Just out of interest, why the mix – an Administration document with numbered headings and numbered paragraphs? I think I used fields for that last time I had to do it in Word, before gratefully returning to my usual environment. Styles might cut it, speculatively, if you had two numbered styles per level: but I'm ready to be told I'm wrong here …