Angry baby...

Has anyone else been through this?? I love her so much of course, but I’m also feeling hopeless. She was such a sweet and easy going baby but about 3 or 4 months ago she turned completely crazy lol... She throws full tantrums (throws herself on the ground, screaming, kicking etc), hits at others, and is just miserable or frustrated basically all the time. She’s only 13 months!! 😅😞 I’m sooooo worn out I don’t know what to do with her anymore. My first wasn’t like this at all. I took her to the pediatrician and he said everything looks fine with her, and chalked it up to teething... but I just don’t think it’d cause it this long and Tylenol doesn’t change it.... please tell me it gets better 😅 I’ve started baby sign language with her cause I thought maybe it’d help, and she knows a few... she’s still so angry though.. ☹️