Irregular cycles are not a sign of a pregnancy but could be the sign of some type disorder that causes sterility such as PCOS. Irregular cycles are typically experienced during menstrual cycles that do not stimulate ovulation. Without ovulation, pregnancy is impossible. Bloating and cramps are also not signs of pregnancy. The first serious sign of pregnancy is a missed period (amenorrhea). Positive pregnancy tests confirm pregnancy and negative tests exclude.

If you have been trying to conceive for several years without success then it seems likely that you are suffering from sterility. The diagnostic procedures for showing evidence of sterility in women are much more complicated than in men so investigations always begin with the man. First your partner’s sperm should be examined (spermogram). If everything is OK with him, you can check if you are ovulating, or not (basal temperature, ovulation predictor tests, measuring progesterone level…). Then you can request an examination of the normal anatomy and the passage of the inner genitals should be checked (ultrasound, HSG, hysteroscopy). It's best that you consult a gynecologist about your problem to seek counsel and necessary diagnostics.