I replaced my water pump for my 2006 buick lucerne and now theres no heat

Hope you didn't break a nail.

There is a air pocket in the heater core, you just didn't burp it right.

Try this

1. Open the hood of your car. Secure the hood with the safety handle. If you have a newer car, you should have a bleeder valve on the front of your radiator. Check in your owner's manual for the location of this valve. If you do start your car, open the valve with wrench and let your car heat up. The excess air will bleed out of your cooling system. Keep your car on long enough to give the (trapped air) time to bleed out of your system.
2. Let your car cool down. Once the car is cool, take off the radiator cap. Did the level of the radiator fluid go down? If it did, it means you bled the air out of your cooling system. Replace the radiator fluid, turn on the car, and let it run. Replace radiator fluid as needed.
3. Step 3 (above) is the way you will remove air from your cooling system if you do not have a bleeder valve on your radiator. You will leave the cap off the radiator. You will run your car until it heats up. As the air dissipates, the radiator fluid level will go down. You will fill up your radiator fluid to the correct level. Be careful because the heated radiator fluid will be hot. Always wear leather gloves and safety goggles when working on your radiator.
4. Once the air dissipates and you fill the fluid, shut off the car. Let the car cool down. Once the car is cool, put the radiator cap back on the radiator. You may have to put more radiator fluid in the radiator. The level may fall as the car cools down. Now it is safe to drive your car. You have removed the trapped air from your cooling system.