"Another" as in, my first, but I see there are some older threads on similar subjects.
In my case it happened after a 12-hour and 6-hour drive on successive days. Woke up in a motel when half-way home with acute right-side pain in the rib area. Managed to get to sleep and drive home, then went to the ER. After several hours of checks and tests (putative diagnoses included pinched nerves, kidney/vesicular stones, and at one point trapped wind), they found the PE in the scanner. (My regular doctor's comment this morning: "They should have found it within half an hour".) They also found a plausible site in my leg for a DVT, which is something of a relief as the most likely alternative source of minor clots is cancer.
Anyway, this was all two weeks ago. I spent five days in hospital, getting out just in time to go on a week's vacation. I'm now wearing thigh-length stockings every day
and taking Xarelto, the new all-singing, all-dancing blood thinner that is replacing Warfarin (no management required, no need to avoid eating foods with vitamin K, and it only killed a couple more people than the alternatives during clinical trials).