Are there any tell-tell signs that might indicate that I might be bipolar?

I’ve been doing some research into depression lately, and I have come up on alot of information that points towards Bipolar type 2. I was wondering if anybody has had any experience or actually knows if having constant ups (good days) and then downs (bad/horrible days) is a indication. For at least the past 3 years, the thought of death has been on my mind, even though I have had no life or death experiences, there are days when I feel like the smartest, talkative, energetic person there ever was, then there are days when I have zero motivation to do even the most mundane task like turning on my xbox to play my favorite game or even talking to ANYBODY. Any feedback would be GREATLY appreciated, everyday I feel like theres something wrong with me, but I’m the only person that feels it.