Hi and you definitely need to see a doctor right away. It could be a brown recluse and this can cause lots of problems if not treated. It could be an infection as well or reaction to the venom.
mkh9
Please see a doctor - and do it soon. Spider bites can become badly infected and what you describe sounds like you've got an infection brewing. An urgent care facility should be able to help you without it costing an arm and a leg.