Keeping A Realtionship

Being a teen mom and being with your baby's father gets frustrating. My relationship with my boyfriend/baby's father gets frustrating and there is a new fight everyday  It goes from helping out with taking care of our baby for example feeding or changing his diaper to not helping out financially. Im 18 and never had a job before so now that I have a baby its even harder to get a job when I really need it. I hate having to depend on my mom for formula and soon diapers. I dont want to put my baby daddy on child support because he works at Wendy's which really doesnt pay that much and then to top it off he has another kid with another girl and she has recently put him on child support (which is really pointless because she doesnt even use that money for the baby she uses it for herself and then she bitches at him for not paying for anything). I know hate is a strong word but I definately hate her, therefore I dont want to put him on it. I know when he has a better job he will pay for things for our son.

Back to the relationship talk.... We have been fighting more and more everyday ever since we found out I was pregnant. I know he loves me and our son but sometimes it just doesnt seem like it. He doesnt show it like he used to. Another problem that has a lot to do with our fighting is that we were dating only for 3 months before I got pregnant so we didnt get to know eachother all that well. And there is no trust. I trust him for the most part but hes been hiding his phone and every time I grab it he goes nuts and does everything he can to get it back. Does that mean hes hiding things from me and cheating on me? I need help because Im starting to lose it and ive been keeping it in this long and I dont think I can handle it anymore. He has confessed to me that he used to cheat on his 1st baby momma but swears that he has never cheated on me. I need advice.

I love him and my little Anthony and I dont want to lose him.