Sharp pains

I'm on CD 34. I O'd on the 29th I believe since I had a +OPK on the 28th. AF is due on the 13th (Monday) and my pg test this morning was negative. However my periods usually flex during the week it's due so who knows when it will really come. Anyways, this morning I've had some sharp pains in the vag area. I've only had two periods in three years (the two being those in Nov and Dec after getting my mirena out) so I'm not 100% if this is AF pains or maybe pg pains? Any opinions?? The only other real symptoms I've had is I've been a little gassy.