Anxiety

Anxiety, what is it? How do we know if we suffer from anxiety or if it simply 'life ache' 
A psychologist once told me I have a bit of life ache. Personally I think that person was full of shit but we won't go into that. 
If fears are preventing someone from carrying out activities their daily life expects of them, I think that is when anxiety is more than an ache. 
Im not an angry person, I never say a bad word to anyone. I couldn't live with myself if I ever hurt someone simply to make myself feel better. 
When anxiety gets the better of me, I become so frustrated with people and feel this urge to tell them how I feel. I feel the need to vent my frustration and tell them that what they are doing is not ok. Though, I never do. 
It's a weakness I have, I choose to bite my Tongue because nothing is ever worth upsetting someone or some situation. 
When I was younger and starting to grow up, I'd get angry at my parents/teachers for minor things.. As we all do. But I would never ever tell them, I'd tell myself that no matter what, I need to accept what they say and move on. This is usually when I'd go to my room or be alone, collect my thoughts, use bad language in my head and to myself and then get over it and move on.
Now, I'm an adult, I haven't changed. I'm proud that I never told my Mum I hated her because it wouldn't have been true. I'm happy that I was a resilient child and never let others opinions bother me. 
However, I am now living a compassionate life but its at the cost of not having  the ability to know when others are taking advantage of me or knowing when I'm being treated like a child.
So my question is, when I have these moments of frustration, is this my anxiety? Who really knows, all I do know is it can't be healthy to suppress that sort of frustration. This is where I'm left to find an outlet, another option.. For me, at this stage of my life, it's meditation. I just hope I can use this weakness and turn it into a strength. After all, that's all we can do- aspire to use negatives to somehow form a positive
Love & Hugs xo