Walk-in clinics, by definition, suck. However when you're desperate and suffering, you just need to inhale slowly and be patient.
For an indication of the wait: on a Friday, I arrived at 8:20am, and was put in a room (still waiting for a doctor) by 9:45am.
Fellow patients were nice, not nagging the staff, and we all know we mutually benefit from happy clinic staff who have our lives (well, schedules) in their sanitized hands.
I ended up having *a very positive experience* because my doctor (and older gentleman), after having asked me whether or not I had health insurance, gave me samples of what otherwise would be a very very expensive prescription. He also wrote me a prescription in case I ran out when I told him how difficult it was for me to take off work, so that I wouldn't need to make a return trip.
All I can advise is arrive early and bring a snack/bevvy so you don't become that gnarly monster whose sighs are overtly loud and who harasses the staff to everyone's dismay. Hopefully you'll get my thoughtful doctor!