Guessing you didn't rinse your pasta. Looks like you cooked it too long and then didn't rinse it and it continued to cook. Just because you drain it doesn't mean it's done. Also looks like you put it back on electric stove burner that was still hot?
Anyway, rinse your pasta with water after you drain it. It will remove the outer layer of starch, stops it from cooking extra, and keeps it from sticking in the pan.
pour some oil in the water while it's boiling.
how many boxes did you use? that looks like 4 boxes or some shit lol