I had severe endometriosis and never would have known it except that an unrelated issue of fibroids caused me to bleed heavily for more than a month. When they went to do surgery for the fibroids they found I had (as they suspected from ultrasounds) VERY severe endometriosis all over my innards (ovaries, outside uterus, stuck to my intestines) and wondered how I didn't suffer at all with cramping or pain. But Endo is very often a cause of infertility and a lot of women with most severe cases don't even know it. I am not sure that is what you have at all, because I never had the cycle problems you are describing, but I did go on low dose birth control to control it after my surgery and had non stop break through bleeding which was annoying and made me stop pills).
My point is that if you do have insurance, most of the "Diagnostic" work that is involved in fertility is covered by insurance, so that part shouldn't be too difficulty financially. I do recommend that you go see an ob/gyn though, not sure if you are seeing a primary care doctor or general practice, but if you don't go see a Reproductive Endocrinologist, at least get to an ob/gyn. If they think you need it, they will refer you to an RE and the initial diagnostics will usually be covered by insurance.
I think you can find cheap OPKs online, maybe some women on here can offer suggestions. I bought some that were like $20 for 30 or something although I never liked them and they didn't help me when I was ttc naturally. Clomid is actually pretty cheap with insurance, I think I paid like $20 for it and then had to pay for monitoring during the cycle (ultrasounds). I only took 3 pills of clomid for each cycle I tried (twice).
1) Ask about bloodtests to check your hormone levels and cycle
2) Ask about possibilty of ultrasounds or HSG to check on your reproductive organs-the benefit of the HSG is that because it injects a contrast dye into your uterus and tubes, some blocked tubes get "cleared" by process and women can get pregnant just from having the HSG (didn't happen for me, but the tech said she knew of it).
3) Ask for suggestions on how to improve chances of conceiving naturally and what they recommend for monitoring ovulation, etc