That doesn't look like a tick bite to me, but if you're prone to allergic reactions, your doctor can give you better things to carry than Benadryl. Carry enough gun as it were.
Oh, once you see a bug crawl on your permetherin treated fabric and just fall over, you might find some peace of mind. Fresh Icaridin repellent is similar, but apply it like deet every few hours.
Edit: I just have to add, no worries
RL1, it won't wreck your shades and bling like nasty deet either.
In my case by bug I mean one scorpion, one spider and one MOAB tarantula hawk wasp. These aletherins work.