Depending on your internet service provider and the network loading, you may find periods in the day where response is slow and times out. So many people streaming movies and such. Evening time here, things can slow to a crawl, even though I have a fiber connection.
So far I haven't seen any problems loading pages here, and I'm usually online most every day.
You might try different browsers. Chrome might be the best for you where you are running XP. I still have an XP notebook, but never use it on the net. It is dedicated to a flat bed scanner that won't work on anything newer than XP. I use both Win 10 and Win 7. I don't see any real difference in speed between them. I generally use Firefox, but there are some websites that just won't behave on it, so use Chrome for them.
Tom