Re: First fight, first loss!
Hiya mate, didn't watch it because videos use loads of data up on my dongle but I'll get round to it.
The main thing I'd say is listen to your coaches. I lost my first one by stoppage, what I did with a coach was video myself doing basic punches i.e. the jab etc. to see if there was any tells, or if I was making any mistakes. Turns out I was dropping my none punching hand when throwing the jab (watching back my first fight it's that what got me KO'd) and I was raising my left before jabbing. Most people have a tell before a jab, you even watch the pros mate, most of them do.
Next thing I'd say is, push yourself that extra mile in training, if you know you should be running but feel like you can't be arsed, just do it anyway or if you know you shouldn't be eating a chocolate bar or having a take away, resist the urge until it goes away. I've found having a rest day once a week helps, however don't got too mad, just a chocolate bar, some crisps a bottle of pop, not drinking beers and take aways etc.
Don't be too hard on yourself, many great fighters have lost their first amateur fight, Joe Calzaghe is one off the top of my head. Everybody who steps in that ring is a winner in my eyes so stick with it until that first win comes mate, don't be too hard on yourself. Only had 7 fights myself (won 5) but I hope my advice has been a help.
BTW when you get that first win, it really is one of the most amazing feelings mate, you'll be glad you did all the hard work WHEN you get it. Stick in mate!!!