[mothered]

my pc is at 4mb download & 3mb upload, but its old lol

Though, It's testing your Internet connection and not the performance/latency of your PC. It should register a better speed than that.

In terms of the result on your cell phone, It's a pretty good Improvement.

My pc might has old hardware, maybe it has a max upload & download speed idk

Make sure that nothing Is running In the background (example: antivirus updating), and then do the speed test.