Is this covering letter ok?

[seraina]

Hello! These are two paragraphs of my covering letter. It would be great of somebody could correct them. I'm particularly unsure about where to put commas. Does the last paragraph sound overconfident?
Thanks a lot in advance!


During the last three years of my studies I have become particularly interested in the field of -----. I have taken several courses on related issues and am currently writing my BA thesis as part of a seminar on -----. Furthermore, I had a rigorous training in statistics and social science research methods.
Beside my studies I gained work experience in two different NGOs. My duties mainly included secretarial tasks such as maintaining databases, drafting articles, or making arrangements for meetings and travel.
-----
I am very interested in this internship position and confident that my knowledge and my administrative skills would be an asset to your organisation.

[David L.]

Over the past three years of my studies I have become particularly interested in the field of -----. I have taken several courses on related issues and am currently writing my BA thesis as part of a seminar on -----. Furthermore, I had a rigorous training in statistics and social science research methods.
Besides my studies, I gained work experience in two different NGOs. My duties mainly involved secretarial tasks such as maintaining databases, drafting articles, and organizing meetings and travel arrangements.
-----
I am very interested in this internship position and confident that my knowledge and my administrative skills would be an asset to your organization.