You always assume that you did something wrong: and end up being hard on yourselves, and having a lot of regret for a long time; without realising that it could be others' mistake too and no fault of yours; according to Dr Ramani Durvasula
You apologise all the time: even when you are not at fault
Toxic self-talk: The way we talk to ourselves in the head makes a lot of difference. When you start using words such as stupid or dumb for yourself, it reduces your self-confidence and self-trust
Undercutting your abilities on a regular basis: constantly in front of others, will drop your self esteem making yourself feel incompetent and to others as well
Undermining your achievements: may feel like being humble for some time, but it will also make your achievements look small