Search Results: when should a guy stop pursuing a girl

This guy is 18 and a senior in high school. He is a dishwasher/busser at this restaurant I work at and I’m a server. Let’s call him - Jake. I went to school with his sister (I’m 21 but look 16/17 years old) and she used to bully me. I don’t think his mom really likes me since I gave her an attitude a few months ago because I was having a bad day (works as a manager in this building but different department). We both have been at this job for 3 months. A week after meeting him I tried talking to him but he didn’t seem interested in me so I stopped and kinda gave him dirty looks at the side eye. However - within the past two weeks he has been more talkative than ever. (He never talks to anyone). He holds doors open for me, randomly stands behind me or very close to me, has bumped into me, always looks at me every time he passes me with a shy grin on his face. Today was exceptionally weird, he bussed every table and reset in my section and nobody else’s (he usually stays in the kitchen and doesn’t bus tables) and was standing very close to me putting dishes away or restocking shelves. This girl bumped into me and spilled soup on me and I was like really and she’s like sorry it was an accident and he’s like an accident? You practically threw that on her Veronica and looked shocked and I just walked away to clean myself up and the girl came up to me and was like I’m sorry and then she’s like Jake needs to mind his own business. And he kept staring at me from a distance and when he talks to me he stares in my eyes with his head bent to the side a little bit. At the end of the shift he stood right next to me on his phone and held the door open as we walked out. He did (does?) have a girlfriend but the last picture they took together was on February 19th of this year, not sure if they are still together or not (found on Facebook). Not sure if he likes me or is just all of a sudden being friendly and open? Should I pursue or I don’t know what to do?