Help!

I'm finding conflicting information. What is considered a normal "safe" leutal phase? Could having an iud removed 4 months ago cause a lp of 10 or less days? Does b6 really help? When should I see a doctor? After 3
​Months of 10 day luteal phases, I'm feeling discouraged that I don't stand a chance at conceiving because there's not enough time to implant! (I realize that in the grand scheme of things, 3 months ttc isn't a long time and that others have been trying for much much longer. Not wanting to offend, just curious and wanting some advice) Thanks Ladies. xx