The two scenes Mooky posted about came and went, and I didn't have to pee yet, and I didn't have to pee until near the end, so I just held it.  But those articles hopefully will be super-helpful for others- I was not the only one at work today worried about our bladders! 
 
I enjoyed this movie a lot!  
Mooky wrote:Are parallel realities created instead? But the Ancient one specifically warned them about that and that they needed to straighten the timeline back by bringing the stones back to their original timelines.
I'm always confused with 
time travel in movies.  But 
Bruce did say that the stones have to be placed back where/when they came from, or else there will be alternate realities (I remember that correctly, right?).  Coming out of the movie, I told my husband that I was confused about the timeline, but he said that for the un-snapped characters, they were 5 years ago (so their "old futures" can be totally changed), whereas the snapped characters had been turned to dust, and they remembered that part, but Doctor Stange told them they had been gone for 5 years, and they went back to help...).
D82 wrote:Though the ending is bittersweet. I think you leave the theater with more sadness than happiness.
I don't feel that way- 
I mean, I cried over Tony, but he saved the whole wide world.  He died so everyone can live.  My biggest end thought was, Where is Gamora?!  I'm betting that Guardians 3 will be a search for her.  I felt that way after Infinity War, though, but I mean most people lived.
Mooky wrote:50% of his high school classmates prior to infinity war - the 50% that survived are all now 5 years older. while the 50% that disappeared are still the same age and are still in high school
I was pretty much following until this point. I don't understand that part.
I absolutely loved 
that Bruce/Hulk played such a big part.  He's my favorite Avenger, so I was very pleased.  And OMG Thor.  Loved it!!!  I'm sad about Tony, of course, and I'm sad about Natasha, of course.  When she & Clint were fighting, I just knew that she'd be the one to sacrifice herself, since he has a wife and kids.  Her movie has to be a prequel, then, huh?  Thor & Cap fighting Thanos together was great.  Rocket was really funny as always.  Peter & Tony's moments made me cry.
Like I said, I really enjoyed this movie.  There were times when I just clapped or "yay"'ed or loudly gasped in the theater during the movie.  I was into it.  I feel like it had a lot of ground to cover, so obviously not every character was highlighted as much as others, just as in any Avengers film.  But it set out to do what it did, and it was satisfying.