Staph infection

[Rywol]

So a few weeks ago I got this big boil on my waist that was like an ingrown hair and eventually after about a week went away on its own. You could still see discoloration there but there's no bump and no more pain. However, now I have one on my butt and it's almost the same thing. So I went to the doctor and they told me that it's a bad staph infection and they prescribed me Bactrim. Before I took it the boil was very painful and it hurt to even sit down. I'm on day 3 of the medication now and the pain is no where near as severe, as now it's just kind of an uncomfortable feeling. But not painful. However the bump is still there. I'm just wondering if that's normal to have after 3 days. I take 2 pills a day one in the morning and at night. I'm only 18 years old if that adds any more information nexessary.

[Rywol]

I'd also like to add that when I'm laying down and stand up sometimes it has a pulsating pain like as if there's lots of pressure on it. But it only lasts for a few seconds and then goes away and it seems to be the only real pain I have now