Anyone get mastitis while on antibx for mastitis?

Seriously?  First off, breastfeeding hasn't exactly been a walk in the park for me and on several occasions I have questioned whether or not I want to continue with it.... and I keep coming back to yes, I really do want to BF.  I have been lucky in that I have managed to EBF DS, no formula to date (woot!), and he's growing like a weed.  But I am not sure if I am going to be able to keep this up... I am currently being treated for mastitis again (second time in 2 weeks, reoccurred in the same spot as last time) and I think I am getting it again in my other breast, even though I am still on antibiotics!  The entire outter aspect of my left breast has been getting progressively more sore as the day has gone on and I think I am starting to feel "sick" again... achy/headachy... just waiting for the fever and chills to set in.  Ugh. 

Has anybody else experienced this?  

I am hoping it's just a clogged duct, I can't really feel a lump or anything though, just really tender to the touch.  I am trying to nurse DS frequently (which is hard though because he only nurses on one side at a time and my mastitis is in the other breast and I need to nurse him frequently on that side) and I just pumped that side while doing TONS of massage/compressions over the affected area.  I have had a heat pack on it for the last hour and will keep it there until I nurse DS again in about an hour. 

 What else should I try for a clogged duct?