1. How tall are you? If your BMI is less than 10% that may be why you aren't having your period.
2. Between tricyclin and yasmin, tricyclin will probably make for worse "moon fluctuation" because it is tri-phasic, which means it has 3 different levels of hormone depending on what week your are on. yasmin has the same level all 3 active weeks.
However, if you are going to choose a low-dose mono-phasic pill there is no reason to jump straight to yasmin. Yasmin and Yas are new types of hormones that other pills don't contain, but that does not necessarily mean they are going to be better for everyone. These two are still under "brand" name and therefore will be many more times as expensive for you than another option. I take the generic version of "loestrin FE 1.5/30" which contains a low dose of hormones and iron on the "off-week" to help with fatigue and iron deficiency anemia which is common for women. On this pill I have my period every month, so I don't freak out, but usually for only 1 day!!! YAY! My cramps are much better, and most importantly my mood-swings (boyfriend calls them my "crazies" haha) around that time are much less severe.
One more thing, for birth control pills, every woman is different. If one isn't working for you and is giving you side effects, headaches, mood problems etc. Just try another one! there are so many. Also, once you start one you need to give it at least 3 cycles before you decide if you like it or hate it, because your body will need to get used to the pattern of hormones that its getting.
If you aren't having your period, get a pregnancy test!
Also, many women have anxiety, depression, insomnia etc. related to their cycle. In addition to a stable, low dose of birth control pills, another thing that may help you is a low dose of an SSRI (which is a family of anti-depressants that increase serotonin levels in your brain) examples of these are prozac, paxil, celexa etc. all of which are generic = cheap and can help tons with PMDD. Prozac specifically (paraoxetine is the generic name) has been studied extensively for PMS/PMDD and has been shown to help many women. If you are having these problems, there is no reason to suffer. Talk to your doctor about it. Also, having your "hormones tested" to see what is wrong with you is likely not needed besides testing for pregnancy.
Also: If you are still sexually active, you should be using the pill, patch, etc. If you think you are a ball of nerves NOW just imagine if you actually got pregnant before you where ready. Don't risk it! Also, make sure you are using a condom to protect yourself from STD's because a pill won't ever do that. I work at an HIV clinic and i see W-A-Y too many young people who come in with newly diagnosed HIV. It breaks my heart every time and I want to sue the public school system for not educating kids better.
Typically, your period should start again within three months after you stop taking the pill. Most women ovulate promptly and have a period within four to six weeks. But some women, especially those who took the pill to regulate their menstrual cycles, may not have a period for many months.
If you don't have a period within three months, take a pregnancy test to make sure you're not pregnant. If after six months you still don't have a period, see your doctor.