Well, putting ice on it and taking an anti inflammatory was probably the smartest thing you could do at that point. I would also take extra precaution to keep it elevated as well and just plain take it easy for a few days. Is the area swollen or warm to the touch?
I haven't had an injury like this one. Mine have all been under that patella (kneecap) Certainly if it inhibits you from walking normally or just the thought of walking on it causes you to wince make an appointment to see your doc.
When you are ready to resume your lower body workouts I would suggest doing squats, step ups, supported split squats (holding onto something in front of you if you can with no additional weight) dumbell deadlifts and maybe even one legged deadlifts as well. Its not until you have been able to master all of those that I would consider adding lunges.
Lunges are a great exercise. They recruit a lot of lower muscles all at once but also rely upon stability on one leg as well as your core strength. When it is time to do lunges maybe backward lunges first and then even forward lunges.
In my own personal experience of recovering from menisci surgery I found that I was able to do all of the before mentioned exercises with a lot of additional weight long before I could do lunges. In fact, the surgery was in January and it was
April or May before I was able to do my first real lunge. At this time, lunges are hit or miss for me. Some days I can do them, some days I can't. But with all the other methods for targeting your legs I don't really miss them if I can't do them during a particular session.
Good luck. Hope you are feeling better soon.