It could be if this is a long-term or recurring pattern for you (i.e. if this is typical for most of your adult life). If it's only a "phase" and is not typical for you, then it's not necessarily indicative of a personality disorder. Everyone overreacts or reacts strangely sometimes, especially if they're not feeling well for whatever reason. It's only if it's a pervasive and stable pattern that it's indicative of a personality problem.