One of the most common regions for blood clots to occur is in the groin area. Symptoms to look out for in terms of blood clots in the groin include; swelling of the leg, leg pain and skin discolouration.
The swelling or redness usually occurs around the same area as the clot, so if it's your groin that is affected, then tenderness my affect your thigh or may even travel to your calf.
When the clot actually breaks off and gets carried through the blood stream, other symptoms begin to arise, including; shortness of breath, sweats, fatigue, rapid heart rate and feeling faint, among others.
Patients could experience all, or some of these symptoms.
This information I have found is derived from the Indiana Hemophilia & Thrombosis Center website, and should not be construed as professional medication advice though.
If you are experiencing any of these symptoms at all, you should see a doctor - that is the safest and most logical thing to do!
Sometimes it is just better to be safe rather than sorry. Although there's no reason to jump to conclusions, speaking to a medical professional is the best option - especially when dealing with something as serious as a potential blood clot.