Clouds gather before a storm.
Anger and aggression are two emotions often linked together and confused as one. Anger is, in fact, a very natural, healthy, universal emotion. Everyone gets angry at some point in their lives if anger is not expressed in a controlled way - maybe you keep your anger inside - then this can lead to physical and mental disorders such as depression, which may well be a result of anger being turned inwards. Not letting it out and allowing it to build up into a much bigger situation could become destructive.
Another result of withheld anger may be an issue with digestion, such as comfort eating which might seem small, but can result in much bigger problems later down the line.
Anger needs to be expressed in the correct manner and at the appropriate time. Holding in anger can eventually show itself as aggression. Aggression is a short-term fix to a situation but without actually concluding any issues where expressing anger correctly can harvest a much better, clearer, forward-moving result.
Pent-up anger can often explodes in an aggressive manner in a situation that has no relevance to the original set of circumstances that made us first feel angry (deferred anger). Anger is a feeling, aggression is a type of behaviour. Being angry is good, but it has to be expressed in the correct way thus avoiding aggression. You can show anger without hurting someone, emotionally or physically. Feelings of anger are not realised through aggressive behaviour.
Anger may have been with you for many years, for example, a family dispute from the past, or anger from something current. I can work with you to realise, understand, and express without aggression by looking at things such as negotiation, confrontation, attitude change, psychotherapy, and forgiveness.
We can explore the origins of your anger whether it's coming from yourself, the past, lifestyle, relationships, or being in a particular situation that may trigger your ager, the list goes on.
It's life, people get angry, but you don't need to be aggressive.