I lift weights 4 days a week. I was wondering if it was ok to do Hiit 3 days a week right after lifting?

no thats a bad idea doing your cardio on the off days is best. otherwise doing it long before/after your workout is recommended.

I am not too sure what Hitt is, but if it refers to cardio you should do it separately from your weight-lifting session. Aerobic training and weight-lifting training uses to different energy systems. You can also focus on each type of training more intensely if you let your body recover from each session.