Ovulation & infertility

Hi there ladies, I'm a newbie here, I will give you here a bit of the story, and then I will explain my question to you, So... Trying to conceive for 8 years, I have Ovarian Cysts, which I heard it is somewhat difficult to get prego, but not impossible, I heard stories of women who made it happen with same condition withing 2-3 years with strict ovulation monitoring... Next thing to share with you is that I also have blocked fallopian tubes, which makes this near impossible to conceive as much as I know, and for 8 years of trying I really did my study, so I lost hope for natural thing, I heard IVF or IUI is possible in my condition, BUT besides lack of money for this, I had hopes for natural way of de-clogging my tubes, before going to use ''last hope'' treatment, there is more than a 100 ways of doing it safely and with 60-75% of chance of success, it does depends of how much clogging is there and there is a trick that the tubes will re-clog after awhile, so cleaning them out before ovulation is very important, (you know cleaning the passage for sperm and your egg , so it can pass through and Bada-boom baby will grow :-) ..I'm not sure if it is going to work and it will for sure take maybe a year or so and it probably will eat my money away quite a bit, but I'm hopeful and want to try this first before going through hormone therapy for IVF and IUI, So the problem here is the damn ovulation.. I used calculator before but I'm not sure if it is that much accurate, I wanted to calculate it myself, but there are out there so many misleading information I'm not sure what is the right tip, For one I heard ovulation is between 11th and 14th day or 1oth to 14th of the cycle, then I found it is between 11th and 21st day, next I saw diagram it is from 12th day till 17th, or 12th till 16th day, and even next info was mid day 11th until 18th day... So which is it ?! I heard Ovulation itself happens only withing 24h, one day, and the rest are the fertile window, (which most fertile is the ovulation day), so all those days are not the ovulation then, but how do I calculate that one important day ? if it is just one day to conceive then it is extremally important to know which day is that exactly, and I have no clue how to know... Please help me,.. I can add that I have regular cycle of 28Days, and I bleed only for 3 days, more like 2 days and 3rd day is more like spotting, not sure if this matters, but I thought it can be important info.

ps. I did not start process of ''un-clogging'' my tubes yet, but started my cleansing cycle few month ago, (a pre-treatment so do speak)
...In result of that "cleaning" or so I think, later on in the month I realized My period was late quite a bit, 2-3 weeks I thought to myself ''no Sh***, I can't be that lucky'' BUT somehow I got hopeful (my mistake) I checked and sex was (based on website calculator) on ovulation day, so when I saw bit pink I thought to myself ''implantation bleed'' ..but it wasn't ;-( ..But could it be ? could I just have a early miscarriage ? ..implantation bleed is 1-2 days and my period is 2/3 days.. small difference, so it is easy to be mistaken.. Or I just saw what I was simply hoping for, after all calculator could be off and that would mean it was just a period.. and I do not know for sure, when I ovulate ugh...!

Any tips, comments are very welcome

xoxox to all trying to Conceive !