Feelings just are. Therefore, your feelings are always valid. This is not to say that they are always logical or that they make sense, but they are always valid.
I often find working with folks with complex and attachment trauma that there are a lot of negative judgements around feelings. This is because of the messages that they got, both overt and covert, about their feelings growing up. Some learned that if they expressed feelings they would get in trouble; some were flat out told that they didn’t actually feel how they felt.
So, helping people learn to identify and feel their feelings is important. It is also important to help them learn that no one can control how they feel, but they can learn how to cope with and express their feelings in a healthy way.
You don’t have to apologize for your feelings, they are valid and so are you!