What Could Painful Arms With Reddish Patches Suggest?

hi,
i'm rashmi(Female)..
i'm 32 yrs old..
yesterday midnight my right arm started aching and within half an hour the pain became unbearable and i was forsed to get out of my bed to reach out a spray or something but i ended up falling unconscious for 30-40seconds during which time myhusband noticed a reddish patch on that arm..
once i gained my consciousness i hardly had any pain and my arms redness was vanished too.
this is the first time that i had such an experiance..
should i take it seriously and approach a doctor or what is the advise?