How to use comma and other signs

I hope you can help me with this sentence, my question is; is the ; , and - correct

During my dissertation I developed my interviewing skills further(<img src="/emoticons/emotion-5.gif" alt="Wink [;)]" /> I constructed an interview protocol, conducted and transcribed six one(-)hour(-)long semi-structured interviews and analysed this textual data in accordance with Grounded Theory.

It looks fine.  Options which I myself would exercise are (1) replacing the semicolon with a full colon ( : ) and (2) placing a comma after interviews (this is called for if the 'listed' items are sufficiently long or convoluted).