What is going on ?

This problem has started getting worse lately and it seriously annoys the F out of me.

So It started around 4 years ago, I mix my words up and swap letter around when speaking, I have no problem writing or anything it's just speaking.

I also say words or phrases that are so similar to the word i'm thinking of and I know what it is and what I mean but just completely mess the words and phrases up and people find it hard to speak to me and it frustrates me so so much because they correct me even though I KNOW what I meant!

It seriously drags me down and makes me feel dumb all the time.

I try to tell people and they don't understand or care and just say I need to read more books ( I use to when I had time A LOT) I was top in English at school it's not like I don't know what i'm talking about it's just the words don't come out right or I can't think of the word which I've used a million times and know which context to use it in.

It's not just a matter of needing to read more, even if I do it still happens and just gets worse or nothing changes.

I'm 22 by the way and i'm just frustrated. PLUS not to mention my memory is extremely bad, I could forget even having a conversation with someone that just happened ten minutes earlier and what was said.

Does anyone have any idea about what is going on ?