Congratulations on your first time: CC
Don't be afraid to not be in a fight all the time you are in the ring; choose the time, place and nature of the exchanges. Pay a LOT of attention to your feet in the next several weeks, and make sure to get your left hip and shoulder turned towards your foe; this will help you avoid many right handed punches.
Here is one last thing to consider: tension exhausts you no matter the level of your conditioning. If you are square to your opponent and thus vulnerable to nearly every punch and holding your hands unnaturally high to guard yourself you will suffer in two ways. First your arms will get tired. Second you will not be able to punch back effectively. Don't be afraid to lower your left to @ shoulder height and to use your left shoulder defensively ala Mayweather, Toney etc...It is actually the most natural way to do it and not some boxing magic. Drop weight to your right foot, turning back over a straight right leg pivoting the left foot inward and going up on the toe to raise the left shoulder. This will intercept the punch and put you in a perfect spot to counter.
Let them lead make them miss and Good Luck