Regressions after sleep training

How do you all deal with sleep regressions after you’ve sleep trained? My son usually sleeps from 7-6 maybe waking once or twice for his binky but going right back to sleep. Tonight he’s already woken up 3 times since bedtime at 7 😳 last night he also woke up more than usual but not like this. Idk if something is bothering him or if we’re entering another sleep regression but idk when to leave him and let him cry for a bit and when to intervene... I don’t want to ruin all the progress we made with sleep training.