Lying In Bed Last Night I Had Excruitiating Pain Suddenly

Lying in bed last night I had excruitiating pain suddenly in my left leg, a stinging type of pain. It didn't last for long but this morning it is sore when I walk. I had heart failure in Jan/Feb this year and am on medication for this including blood thinners, aspirin, BP tabs, etc. I am worried it is a blood clot, can you please advise me. I have a busy day planned visiting gardens so I don't know whether to go or to seek medical attention.