My name is Lilith, I'm on the Social Care team at Shopify.
To help clarify what the analytics mean let's define each of them a bit.
Bounce rate and page load speed are not always related, there are many different things that can impact a bounce rate whereas page speed is just the speed at which the page loads.
Google's support site has a great help page to help you understand what bounce rate is and what is thought of as good or bad. Remember that bounce rate is really only the quantity of visitors that saw the page and left without doing anything else on it.
Page load time is just simply what it sounds like. The time it takes for a page to load on a browser.
If you have a fairly average page speed load time, like in your case, there is not much there related to the bounce rate.
Instead, your bounce rate being at 100% can be the result of the wrong customer target coming to your site and not being interested in the site/page/product at all. It could also be that an ad's promise wasn't fulfilled when the landed on the page, it could also be random traffic that found your site by mistake. It could be due to low-quality pages. Of course, there are tons of other factors that can impact it as well.
An average bounce rate should be around the 50% range.
In your case, I'm not sure what your total traffic volume was nor the date range you used to pull the data. But if you're sitting at less than 1000 visitors in a month for traffic, that can sometimes cause the numbers to look worse since you won't have much data at all.
Think of it this way: if only 3 people came to the site and all 3 bounced that would give you a 100% bounce rate.
Whereas if 100 visitors dropped in and 50 bounced, that would leave you with only a 50% bounce rate. Significantly better even though more people bounced!
The numbers and ratios can make a difference in reading the analytics, hence you'll need to analyze your analytics to get an accurate picture.
Here are a couple of good resources to use when you're trying to analyze your data and how to interpret it in a meaningful way for your business:
Let me know how you do with the information above! I'm happy to answer any questions you think of as you work on your business.