Very slow internet connection on windows 7

I installed Windows 7 on my iMac in order to test a few websites on different internet browsers. and for the first week or so the internet worked fine. But then i started to notice that the internet got Very slow and i went to test the speeds and this is what i got:

Mac: 12.42mbps (good)

Windows: 0.20mbps (***?)

this is ridiculous. the internet just got slow all of a sudden. nothing has changed with my router or anything like that, i would have noticed it on my mac partition and my ipad. Please help me 😟