BPD or just after "one thing"?
I don't know if a guy I recently was dating was showing signs BPD. A therapist said he might.
The guy quit talking to me after I told him he'd need to stop smoking if he wanted to be initmate with me. I mean completely ignored me and even blocked my number. This was after days of talking for hours on the phone and non stop texting.
Before we met in person the guy asked if i ever felt like i knew someone forever (after just talking to them). I told him i have felt that way and have learned to take it slower, and his response was "Lol don't worry I didn't mean anything by it".
I don't know if those were signs of BPD, or if he was just after "one thing", or if he just decided we weren't compatible. I just feel angry he spent hours and hours talking to me then suddenly dropped me cold turkey after i told him he would need to quit smoking.
These are two signs of bpd, however it's hard to know if he really is bpd without a diagnosis from a proper professional, as personally disorders are highly complicated.
Borderlines are known to have struggles with a term called Object Constancy. This means it is typical from them to see someone as completely perfect, and then see someone as completely awful when the image of perfectionism is broken. He also seems to have the typical emotional intensity toward a specific person that many borderlines typically do.
As someone with bpd, I can tell you that whenever I do something like he did, I usually feel regret and shame very quickly after the action. There is many possibilities of what is going on through his mind right now. If he is a borderline, he may be too shameful to talk to you again, or potentially still holding a grudge. As I'm not in your situation myself, I can't give you any advices, but something you can always do is give him some time and talk to him again later.
wish you all the best!
@HoneyDinkley TheBlueBirdie said it well, so I'm only going to touch on one thing. Regarding the smoking situation. As a former smoker myself, one of the worst and most infuriating things was if someone told me to give up smoking. If it was so easy, no one would be smoking. Trying to force someone to stop something that has been a source of "comfort" and a coping mechanism, will never go down well. I'm thinking that maybe that's the reason for him pulling away. I quit on my own terms, and that's the reason I've been able to stop. Someone once gave me an ultimatum to stop smoking or be broken up with. I did it, but it was excruciating, and I started smoking in secret. I eventually started resenting that person. Maybe that's what's happening here. I can't say with certainty, as I don't know what's going through his mind. So this is just a thought based on my own experience. :)
@RayneStorm At one point he told me he only smokes cloves. But then during our first date we passed by a girl that was smoking and i started coughing and telling him i wanted to hurry up and move past her. I asked him if he ever smoked before. He said he used to smoke but doesn't anymore because it's nasty. I couldn't understand why he would say that after he'd already told me he smokes cloves. 
@HoneyDinkley Oh yes, I agree... He shouldn't have lied to you. So that's on him, not you. :)
It sounds like he might just have been telling you what he thought you wanted to hear. Perhaps he wanted to get physical with you but didn't want to commit to anything emotional. I can see how he might have just backed off because you have a strong sense of self, a moral compass and aren't prepared to throw yourself into a relationship without a better sense of who the person is. If that was the case, well done you. Whatever his mental health state is, you took care of you.