to answer your question - should you use hcg post cycle? yes. can you get by without it? yes.
there are other supplements out there you can take. I have had luck with Nelsons products "post cycle" and (I forget the other one that goes with it...i'm sure someone can fill me in here).
also, things like tribulus can be used.
As someone who has beeen using AAS for the better part of a decade and who has multiple cycles under his belt, I can say that I highly prefer to use HCG throughout the cycle, rather than at the end. If you can prevent something from happening in the first place, you then negate the fact of having to deal with it later.
As far as what to use for your first cycle, it sounds like you are dead set on using tren. (hey, I love tren, and have used it several times with tremendous success), thus, I will not attempt to tell you to use otherwise.
whatever compound you use, as it is your first cycle, it is going to work the best (future cycles, will not quite match up - though still highly effective).
Just be sure to eat right (lots of protein), maybe some adex on hand 'just in case'. can prolactin be an issue? it can. will it for you? I cannot answer that. Time will tell.