Why do both my needs crack when my legs are bent to a specific angle (both legs at same angle)? is it connected to my patellofemoral pain syndrome?

Yes, its related to : Your pf joint problems. You most likely have chondromalacia, where the cartilage of the 2 bones become soft due to undue pressure (loading) because of not having normal tracking of the patella in its femoral groove (maltracking). It does occur on both sides. Exercises to strengthen the quads muscles, specifically the vmo would and does improve symptoms a great deal, or surgery might be needed.