Originally Posted by macropod

The F/R is behaving that way because you've specified a Style name for the Find/Replace. Anything replaced that way adopts the same Style. The use of wildcards has nothing to do with that one way or the other. In any event, instead of inserting two extra paragraph breaks after the Heading, what you should do is change the Heading 1 Style's definition so that it includes an appropriate 'space after' value (e.g. 24pt). If you want to avoid the page breaks adopting the Heading 1 Style, do the Find/Replace in two steps: first insert the page breaks; then apply the Style, viz.:
Find = [0-9]{1,}^13
Replace = ^m^&
Replace = ^&
with the second one specifying Heading 1 for the Style.