It could mean that your ex is still curious about your life. Maybe they still have some feelings for you, or they just can't help but be nosy about what you're up to now.
Well, it might be that they're starting to feel less angry or bitter about the breakup. By unblocking you and watching your story, they could be subconsciously reaching out in a very low - key way. It could also be that they're bored and just looking at random people's stories, and yours happened to catch their eye. However, if there were still some good times in your relationship, there's a chance they have some residual feelings and are testing the waters to see if they still care about what's going on in your world.
It depends. If you still have feelings for them and think there's a chance to reconcile, you could reach out casually. But if it ended badly, it's probably best not to.
Personally, I would hold off on reaching out right away. Just because they unblocked you and watched your story doesn't necessarily mean they want to re - establish a connection. It could be a momentary lapse of curiosity. If you do decide to reach out, make sure you're doing it for the right reasons, like if you truly miss them and think there's a possibility of a healthy relationship. But first, give it some time. See if they make any further moves. Maybe they'll send you a message first, which would be a stronger indication that they're interested in talking.
Don't overthink it. It was an accident. Just carry on with your day as normal. If seeing their story made you feel something, try to distract yourself with other activities like reading a book or going for a walk.
Well, it might be that they're trying to keep their distance while still being a bit nosy. They didn't wish you a happy birthday because they don't want to give you the wrong idea that they want to be back in your life in a big way. But watching your story shows that they're still interested in what's going on with you on some level.
It depends on how you feel. If you think there's still a chance for a positive interaction and you really want to clear the air, you could reach out casually. But be prepared for the possibility that they might not respond well. They watched your story but didn't say happy birthday, which could mean they're not interested in a real conversation.