Skin infection, need reassurance

[Traceypo]

Hi everyone, haven't posted anything for a while. I was bit/stung last Monday and it was healing well. Today, the site is angry, red and swollen and about 10cm. Went into full panic and couldn't calm myself, images of Mrsa etc. Was at walk in prior to opening, was given antibiotics to take and doctor didn't seem overly concerned. Now I'm left feeling drained, tired and because it's itchy, I can't stop looking at it, feeding my anxiety more.
Can anyone who's had any similar skin infections please offer me reassurance, fed up of losing days of my life to anxiety. Thank you in advance.