DDT there is so much great information in here to determine if it applies to you,
humidity;
under processed;
roller setting yes to your length (see comment from Knt1229);
misconception that relaxer mean bone straight all the time; (very true)
relaxer not for everyone hair texture;
technique, practices and products;
too much different processing on your hair (texlax, BC, natural, relax...);
leave hair alone from chemicals - braid, wig it, ...;
less styling and more hair care leave that for next year the styling;
evaluate your hair, lifestyle, and image you want to project;
Then to stick to it.
While you determine your course of action, you want your hair to look decent and remain healthy. I guess first decide how you are going to wear it. If as is and you really can't roller set it, I was thinking why not treat it as you were natural /texlax awkward length stage. Moisture your hair and seal, gently pull your hair back with a band until it grows more to do some type of styling WnG. I would forget trying to make it look straight for a while.
Since you need to take care of it whether as is or in braids, weaves, extension, wash etc, technique, practices and products need to be determine. So the million dollars question what does your hair needs? What should your regimen be? I guess with more input from you we can help you on a possible reggie with the styling you decided on and other reggies as it gets to the next stage.
PS. If you go to a salon down the road, unless YOU determine it is damage do not let them cut your hair or you will be starting back at square one and frustration galore. Get some length so you can do something else with your hair and motivate you on wards.