I’m a uni student and it’s just so hard for me to voice my opinions during group discussion and even chatting with acquaintances/friends from uni.
I keep getting those negative thoughts the moment I feel like speaking my thoughts during group discussions. I fear that they think my inputs are redundant to the project, and they are not ‘high-level’. I’m not smart, so maybe that’s why I think that my ideas are not good.
Also, I have very poor communication skills. My thoughts and the words I say don’t match and they get jumbled up. I even tend to stumble and speak very softly. I don’t like the way I sound, I sound boring and dull. This makes me even more scared of speaking as what I say would make no sense, making it very awkward and embarassing.
I really don’t know what to do. I’m trying to think positively, that no one cares or remembers what I did/said at the very end of the day so I should just speak up. However, it’s no use. I still get scared. I clamp up and keep to myself.
Dear @user368536
It is good you reached out to share your experiences in university. I believe you are seeking help because you wish to address this area and want to feel more comfortable and confident in voicing your opinions, without the anxiety you are currently feeling.
I believe this is type of anxiety, called performance anxiety, is actually quite common. Most of us have felt similar to you at some point.. Do not be discouraged, you can become a better communicator. May I recommend the following to manage it 
a)write down short sentences or in point form on what you want to say before you say it. This way you can organise your thoughts on paper first before speaking up.
b)be prepared beforehand. For example read up the relevant topic and be more familiar with it. This way you can follow the discussions better and contribute your ideas. No need to say a lot initially. Start off with short phrases, and listen actively so that you add in where needed and participate.
c)learn from observing your peers who are more confident. How do they put forth their ideas and suggestions? How do they handle arguments or opposing views to theirs? Notice how they speak, pause and use gestures to convey their message.
d)practise speaking up even if it feels scary. Instead of avoiding, take small steps to speak up anyway. Be gentle with yourself as you improve. Ask colleagues for pointers and feedback and if useful incorporate into your conversations and presentations.
Remember you will get better with practice so keep going :).