Many things change when a couple is newly married.
A frank and intimate talk with your new wife (Congrats btw) would be a possible starting place. Is she worried about pregnancy/birth control issues? Does she feel like it's a duty and she "has to" even if she's tired or not feeling well? Is she embarrassed about trying new positions or things you are doing during sex? Is she worried that you might ask for something she's uncomfortable with? Do you communicate verbally while making love? Certain people are embarrassed by certain words even during lovemaking.
Different people were raised with different attitudes about sex. Whether spoken or not, these attitudes often have an effect on other members of the household.(i.e. children, especially during puberty). These attitudes can last well into adulthood.
For example: Was she taught that sex was primarily a way to land a good husband, but then was just for procreation?
A look at yourself is in order too. Ask the same questions of yourself that you do her.
Between the 2 of you, the answers to questions like these may give you a few clues as to the direction to go in making things better.
Also you can assess your technique when you are together. Are there additional things or different things you could do to heighten the experience for her?
Experimenting with different positions may help (if she is ok with that. Some women just can't get thrilled about certain positions while others make them go crazy with excitement.
Give it time and as you become more comfortable in being married, things should get better. Take your time learning each other's favorite things and most sensitive spots (not always the genitals) then use what you have learned to give her pleasure.
From my personal experience, my 1st wife found it a TOTAL mood killer to hear the words c__k or p___y and would stop the lovemaking session. My current wife said that I can say anything I want in the bedroom but she prefers that I do not use certain words in the living room.
You have the rest of your lives to get this figured out even though sooner would be better than later for obvious reasons. Don't push it too hard, but don't bury it away either-it takes two to tango.
anyway there are other options if this doesn't work, don't despair and DON'T FEEL EMBARRASSED! This happens to more people than you realize.