Will google crawl link from jquery .load() from external php file

Will Google follow those links to other pages. or will Google only follow the links on the initial loading of the webpages html.

Short answer: yes.

Somewhat longer answer:
A while back, Matt Cutts announced via Twitter that Google is now able to “execute AJAX/JS to index some dynamic comments”. Google also made an [URL=“http://googlewebmastercentral.blogspot.de/2011/11/get-post-and-safely-surfacing-more-of.html”]official blog post on the subject which confirms this.
Saying that however, there are certain steps that you can take yourself to make your AJAX site more search engine friendly.