4 years ago i went from couch potatoe to lifting a bit too fast so I injured myself. So now I'm completely healed by physiotherapy, and two months ago I started lifting again, it went really fast and I trained hard so I started to lift heavier. There's a red light that went on in my mind, maybe going from couch potatoe to lifting hard and frequently isn't the best idea.
So I went to a gym where they do it hiit classes, and I intend to do it for 3 months before going back to lifting.
Does it make sense?
You don't have to do that. You can be very lean and strong with HIIT classes but get hurt on your first lift when you go heavy.
If your objective is to get stronger and lift heavy, then just stick to lifting. What is important is to learn how to lift properly and how to split up the lifts throughout the week. For technique purposes, there is no better option than finding a good trainer that can help you with this, and yes, you will need to dish out a bit of cash. Shop around. Find a good trainer, one that has experience in powerlifting lifts. Should be your best bet to find a trainer adequate in technique.
Btw, even in HIIT classes, you can still get hurt. Doing 400 bad air squats can be just as damaging as lifting moderate weight on bad form.