Immediately post Botox injection marks noticeable?

I am unsure why it would matter if your dermatologist knows you got botox elsewhere. I suggest going to one place but that is up to you. they shouldn't know.  Best, Dr. Emer.

Immediately after treatment with Botox, it's normal to have some localized swelling (resembling mosquito bites) at the sites of injection for ~30-60 minutes after treatment, but it's not typical to have swelling after that. 

After botox you may have some mild mosquito bite looking bumps for 10-30mins but should absolutely be resolved by the time you see your derm.  Bruising is always a possibility as well.

Redness at the site of injection is not uncommon after Botox.
For most patients, this redness will often go away after a few hours of
treatment. There is a risk of bleeding, bruising, and swelling anytime you are
injected with a needle. Injection marks from the needle perforating the skin
are usually very small or often unnoticeable. Certified and licensed providers,
like plastic surgeons and dermatologists, can provide valuable expertise
related to your Botox injection. Thank you for your question.

Usually, injection marks after injecting the "11's" (frown lines) fade quickly and are not visible in a few hours. However, there is a risk of bruising after Botox as with any injection. It would be prudent to inform your dermatologist, or any other doctor, about your treatments so that he/she has complete information in evaluating and diagnosing any problem and recommending treatments. For example, you should avoid pressure on your eyebrows for 3 days after Botox and if you've had Botox recently, it's something your dermatologist should know, simply to avoid pressure in the area during an examination and in case you have a microdermabrasion or peel which would also entail some pressure on the Botox injection sites.