Knee and foot pain after running

Hello!

I’ve been experiencing discomfort on the inside of my right knee after running the past few times, and now I’m having pain in what I think is the peroneal tendon in my right foot. I run 1:30 minute intervals of walking/running for 30 minutes, with 5 minutes each of warm up and cool down. I do this 3 times a week.

I’m fairly new to running, but I’m a generally fit person. I did weightlifting for about a year before switching my focus to running. I try to keep my chest up and out, shoulders down and back, head forward and I run on the balls of my feet, so I think my form is decent? But I’m clearly having issues on the right side of my body. I’ve never had any discomfort or pain on the left. Is there any reason I’d be having these issues? And what can I do to prevent this? Sorry if this is a dumb question…

TIA