I am in the same boat only difference is that I'm sixteen. The best advice that I can offer is, to avoid talk about the baby untilit is inevitable. At first my boyfriend freaked out and started looking for ways out which included having an abortion, then giving him up for adoption and now he wants a paternity test. During this time with your boyfriend just let him cool down and be lenient on him, let him go out with friends without being upset that he left you for a fun day. Another thing is don't let his actions and words affect you, if he is constantly making you cry then he is also negatively affecting the baby, now things are about the baby because like my mom has told me a million times the baby didn'task to be conceived, it's not he's fault that he exist so why already expose him to so many negative thoughts and feelings? Sad thing is that as much as you love him you need to put the baby first, and consider all options. So in a nutshell just have a tester time period to try to work things out because you love him and for the baby, but if things don't change and you still feel alone and by yourself with no support then the relationship isn't healthy for you or the baby, this way you'll be happy knowing you tried and then as hard as it is you can move on,
Try not to worry. When the baby comes along your main focus will be him/her. As long as that's the focus and you stick to your guts it will be fine, boyfriend or not. Parenting isn't easy any age, you just do your best, and then your a great parent.