S.B.
By xray, do you mean hysterosalpingogram (HSG) - where they inject some contrast into the uterus to take the xray? I had it done in Dec. They do it just a few days after your period, so there's no chance your pregnant yet. My regular doctor had refered me to an RE (Reproductive Endochronologist) as I wasn't pregnant after about 18months of trying. &(The HSG and some blood draws to check hormone levels were the first things they did.) My doctor indictated that some studies have shown an increased pregnancy rate in the first three months after the HSG, if nothing is detected. Sure worked for me - I was pregnant the next month. The theory is that injecting the contrast can clean out some minor blockages in the tubes. Might be less of an issue for you though, since you've been pregnant before. I was nervous for the HSG, but it wasn't a big deal (just take 3-4 ibuprophen beforehand) - it was slightly uncomfortable and a felt a few cramps as they injected the contrast, but that's all. I was almost 34.
As for time to get pregnant, I can't really say, but I have heard that even if it's easy one time, it might be harder the next as you get a couple years older.
Hope this helps.