I'm really worried about when I will ovulate if my cycle isn't the normal length of time
Ovulation takes place 14 to 15 days before your next period. SO, if you get your period every 35th day, your ovulation would occur around 20th day following the last period. I hope you got that! :-)
First day of cycle is considered to be the first day of your period. Your ovulation takes place on 20-21 day of your cycle.
your lutenizing phase may be much longer or shorter than that average of 14 days!!
The only way you will know your ovulation days is by getting a fertility monitor or Basal Body Temperature monitor! Check for signs that could indicate ovulation, nausea, headaches, ovulation cramping, discharge!
DO NOT guess!!! or just "take away 14 days from your period"
Example: (her shortest cycle):27days-18days=9;
(her longest cycle):31days-11days=20
She therefore will be abstinent from the 9th day after the onset of menses to the 20th day
Source: My medical school lecture.
Also there is an app called period tracker which is awesome for telling you when you are ovulating.
I also have a 35 day cycle but I ovulated 17 days before starting.It can differ, best to try every day from 13-17 days, just in case, buy ovulation tests to pin point your's.