You’re allowed to figure out what emotions you’re feeling in broadly the same way you would with anyone else, which is by paying attention to what you’re actually doing. If you’re behaving in an angry way, maybe you’re actually angry.
When there is a lack of interoception, we’re unable to fully feel the sensations associated with emotions. Unfortunately, this means they remain beneath our conscious awareness and instead are projected onto others — or we find ourselves emotionally overreacting in ways that are rarely conducive to our long-term goals.