Slow Loading

I've always been happy with the speed of our database but am today experiencing frequent loading circles when moving around the database.

This has coincided with the import of thousands of product lines (each with about 8 columns of text / price data)

Naturally I'm concerned this is the cause. While I'm trying to keep all business processes in 1 database, might I be best to seperate out my purchasing / products database seperately to the main database - would this improve loading times?

Just want to be sure I'm going about it the right way without hindering performance before investing too much time building links in the wrong place. Or might this loading we're experiencing today be co-incidental. Thanks