Please help me out.

Okay so, me and my boyfriend have been having things hard the last month. We’ve been constantly frustrated with each other and, we both still want to work things out. I was texting him today and he said he needed time to think things through and I freaked out bc I deal with anxiety and immediately thought he wanted to break up with me. I’m trying to be a better person bc I know I cam be unreasonable at times. He’s busy from 8am-5pm bc of work and sometimes, I just expect him to reply even though I know that he probably won’t be able to. I know some of you might think it’s childish of me but, this is my first relationship and, I’m still trying to get the hang of it. Can any one of you give me tips on how not to freak out at every small thing that happens or how to handle my frustrations properly instead of giving him attitude? I just really need advice on how to deal with my emotions better. We have both agreed that we will keep trying till we feel like enough is enough. I have a feeling that it’s going to get better bc my anxiety has died down a lot recently but, it’d be nice to get advice from people I guess. Thank you😊.