Many times the blog page loads slowly
because the blog background,
the HTML which you have set as a Gadget
is located at the top of your blog's Layout.
Move the Gadget with the code to the bottom
of your Layout. See if that improves the load
speed of your blog.
If your blog has a selected background whereby you copied the code and put it in your Layout as an HTML Gadget, you may want to go to Template and see what Background is shown. If it's not the one you installed, just check the Remove this Background box. Be certain that you see exactly what you selected for your blog background and if everything looks okay, click Apply to Blog and then click Return to Blogger.
Humongous images and banners sometimes drag the blog's loading time, too. If there are broken links, these affect the page speed as well as lots of widgets, tools, and flashing items.
With limited time, some readers don't wait for slow pages, and they'll never know how terrific your blog is if they don't stick around for it to finish loading.
If these things apply to your blog, you fix them and it still loads slowly, maybe it's just a bug, a ghostie, one of those unexplainable facets of internet nature. There's a lot of that going around...