Nextjs Custom HTTPs Server is Slow

I am trying to run a Next.js website in production, but the website is really slow to load (~8 seconds to load each page). This is in stark contrast to development, where each page takes ~0.4 seconds to load on average.

I am using a custom server with Next.js to use HTTPS instead of HTTP.

Here is my server code:

const http = require('http');
const https = require('https');
const fs = require('fs');
const next = require('next');

const app = next({
  dev: process.env.NODE_ENV !== 'production'
});

const handle = app.getRequestHandler();

const options = {
  key: fs.readFileSync('/etc/letsencrypt/live/eliotfisk.com/privkey.pem'),
  cert: fs.readFileSync('/etc/letsencrypt/live/eliotfisk.com/fullchain.pem')
};

app.prepare().then(() => {
  https.createServer(options, (req, res) => {
    handle(req, res)
  }).listen(443, (err) => {
    if (err) throw err
    console.log('> Ready on https://localhost:443')
  })

  http.createServer((req, res) => {
    res.writeHead(301, {
      Location: `https://${req.headers.host}${req.url}`
    })
    res.end();
  }).listen(80, (err) => {
    if (err) throw err
    console.log('> Ready on http://localhost:8080')
  })
})

Is this just a limitation of my server hardware itself? I am using a DigitalOcean VPS to run this server.

Also, I feel like this has to do with the build of my server, because when I run server.js, it says that it is compiling the pages, and I feel like this should be in the build I already created.

I have already ran next build, but I don't think the custom server is using this build.

Here is an example of the logs:

joey@WebsiteDroplet:~/Website$ sudo node server
info  - SWC minify release candidate enabled. https://nextjs.link/swcmin
event - compiled client and server successfully in 2s (196 modules)
wait  - compiling...
event - compiled client and server successfully in 292 ms (196 modules)
> Ready on https://localhost:443
> Ready on http://localhost:8080
wait  - compiling /_error (client and server)...
event - compiled client and server successfully in 436 ms (197 modules)
wait  - compiling /about (client and server)...
event - compiled client and server successfully in 486 ms (205 modules)

When I was running the custom server, the dev option in the next function was unintentionally set to true in the line:

const app = next({
  dev: process.env.NODE_ENV !== 'production'
});

For production, I set the environment variable in the next.config.js file like so:

module.exports = {
  env: {
    NODE_ENV: 'production',
  },
}

As documented on the Next.js docs.