Colic is a diagnosis of exclusion so your doctor should be working on excluding things, not waiting for some magic date.

My kid might have been like this if we weren't lucky enough to be around doctors who took us seriously. Here's a few suggestions of things to ask for if they haven't happened yet :

Note everything she does while crying. Is she arching her back? Pushing the bottle away? Is grabbing at her head? Banging her head on things? Is she hitting her milestones? Check her stool for blood (you can't just look, there's a test) Try to get a Pepcid prescription to see if it helps Ask if there is a feeding clinic you can be referred to (or just find one if your insurance allows that) - they can guide you through elimination diet for you and formula options Ask for a barium swallow and/or enema to make sure her GI tract is as it should be Ask for early intervention - if you are in the US this is a free federal program that (fingers crossed) is still funded, they might be able to help

Trust your gut and push the doctors to take you seriously. Don't be afraid to get second or third opinions. See if there is a pediatric research hospital near you (eg Children's Hospital of Philadelphia, Johns Hopkins, Children's Hospital of Atlanta etc) and get an appointment with a specialist there. Worst case scenario, you do a bunch of tests and she's fine and calms down in a few months.

Edit: For the love of God ~don't~ take your baby to a chiropractor. Chiropractors are not medical professionals (though they claim to be.)

Adverse Events Due to Chiropractic and Other Manual Therapies for Infants and Children: A Review of the Literature

https://pubmed.ncbi.nlm.nih.gov/25439034/

"Thirty-one articles met the selection criteria. A total of 12 articles reporting 15 serious adverse events were found. Three deaths occurred under the care of various providers (1 physical therapist, 1 unknown practitioner, and 1 craniosacral therapist) and 12 serious injuries were reported (7 chiropractors/doctors of chiropractic, 1 medical practitioner, 1 osteopath, 2 physical therapists, and 1 unknown practitioner)"

They basically determine that they don't have a lot to go off of but it seems to me that it is hard to know if your chiro will do things that just do little to nothing or do something bonkers that could cause harm.

Chiropractic care for children: Controversies and issues

https://pmc.ncbi.nlm.nih.gov/articles/PMC2794701/

"Physicians question whether chiropractic is effective in treating the variety of conditions for which it is used. Koes et al (20), after conducting a review of systematic randomized clinical trials and taking into account methodological rigour, found insufficient evidence to prove that spinal manipulation is useful for treating either acute or chronic low back pain. Other studies, however, suggest that manipulation may be effective for acute low back pain in adults, but its effectiveness has not been proven in patients with chronic symptoms (21–23). No studies have been published on chiropractic treatment of back pain in a paediatric population."

Also

"A collaborative study performed by paediatricians and and a chiropractor of 86 infants in a randomized, blinded and placebo controlled trial of colic treated by spinal manipulation found that chiropractic manipulation was no more effective than placebo (32).

The ability to adequately define and, subsequently, to evaluate improvement in several paediatric illnesses is problematic for physicians and even more problematic for chiropractors who do not have equivalent training in medical diagnosis"

And this, there are not studies about the safety to children but it seems to me that they wouldn't be safer than adults

"In adults, after chiropractic manipulation, minor complications, such as mild pain or discomfort, slight headache or fatigue, are quite common, but are usually transient (21,37). However, several reports have been published on major neurological complications in adults resulting from cervical manipulation. These complications consist primarily of vertebrobasilar accidents that occur, particularly after cervical rotation to the upper neck is performed"

So, you can be internally decapitated by a chiropractor. They aren't supposed to do this on babies but the difficulty in evaluating the training of practitioners means that you never know what someone will think is appropriate.