Question Help with broken ethernet card

Apr 3, 2021
Last week I bought an ethernet card for my computer (a Realtek gbe networking card ) it was working alright until I noticed that my internet was maxing out at 10 MB/s (usually I get 90 MB/s) and I tried changing the duplex to gigabit which did nothing , I talked to my friend who studies IT and he said it might be slower because the card was connected to a pcie x1 slot and I should try connecting it to a pciex16 slot instead (I have an MSI x370). I tried that and noticed something was off because both the slot I connected the networking card to and the slot my gpu was connected had a white led turn on underneath the plastic clamp at the end of the slot and when I logged into my account the internet would go in and out (on for a few seconds off for a few seconds). This persisted when I moved the card ack to the original slot and when I look at the networking center it says that it doesn't detect a plugged in cable . Did I brick my networking card by accident ?