I have been using the duolingo app for along time, but I would always forget to use it. Now I have been doing many lesson a day. Is it helpful to do it this way or should I slow it down?
Do as many as you feel comfortable with. Everyone learns at different paces. But don't overdo it where what you learn doesn't sink in.
So long as you continuously review, you should be fine. If you are doing several lessons a day and don't review it the next day, I don't think you will retain as much as you would like to.
Do as much as you want every day but keep it consistent. Try to keep a streak going!
I also tend to binge, so I decided to give myself some structure. My strategy is no more than 1 full skill circle per day (no matter the number of exercises within the skill), but then all the timed reviews I want. (Timed review is the way to go, btw. So, so helpful. Buy it from the lingot store if you haven't already.)