I'm a STEM major, college sophomore, looking for an internship this summer and a place I'm applying to needs 3 references, after I finished my interviewed there. I tried contacting my manager from my intern position last year asking if she'd be a reference. Problem is she didn't respond after a week, and I'm afraid she doesn't like me all that much. I definitely did do things there that I regret, like spending too much time on non-work related sites, and I'm not too sure if she was aware of that or not, but I felt like I could've done better without the distractions. So anyways, I'm afraid this might screw up my chances for an internship this summer. Who else should I ask as references? Are 2 TAs from past courses and perhaps a coworker last summer be good enough? Anything else could I do? How bad of a position am I in in terms of getting an internship this summer, or that internship position in particular? For that particular position, I did feel like I aced the interview, so that's the one thing I could see really going for me.