My monthly USED to be regular (every 26 days to be exact). Ever since I had my Son, my monthly has NEVER been regular. One month it was 27 days another was 26 and this month was 23 days. ARGH! We plan to try for another baby in January, but it will be so much harder if my monthly isn't even dependable :(
It shouldn't be too hard to get pregnant, your cycle isn't that irregular. Mine use to range from 28-31 days and it was still pretty easy to time things. Make sure you have sex on day 10, 12, 14 and even 15 of your cycle. Sperm lives in your body for up to 3-4 days and that would give you plenty of coverage.