My Marty is acting strange lately

Hello my guinea pig Marty sometimes falls over today. He's still eating but he's not squeaking really but just so low energy from the past few days. I got him some antibiotics from Amazon because I saw insta reels and the reviews were good. I just gave him some today. Is there a good chance my Marty will be fine even if I take him to the vet. Last time with my Hermes I took him to the vet and he unfortunately still passed a few days later. Please any advice helps